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QB019 — Geoff McDonald and Associates Pty Ltd

QUAD B IKE SAFETY

In Search of Good Theory

‘There is nothing so practical as a good theory’ (Kurt Lewin, 1936)

by

G. L. McDonald M.E., B.Sc.FIEAust, FSIA, HFESA, WSO-CSE

26th September 2012

TABLE OF CONTENTS

Page No.

QUAD BIKE SAFETY Judgement Pair

11

PERSONAL BACKGROUND AND SHAPING 2

SCIENTIFIC METHOD AND USE OF ‘GOOD THEORY’ 5

IDENTIFYING THE GOALS FOR SAFETY Relevant Industry Experience

711

RELEVNCE OF TRACTOR ‘ACCIDENT RESEARCH’ 19

MANAGING QUAD BIKE SAFETY 23

TRAINING AND BEHAVIOUR CONTROL 27

FACTORS WHICH AFFECT HOW, WHERE AND FOR WHAT PURPOSE A QUAD BIKE IS RIDDEN Arousal Visual Perception Information Processing Decision Making

28

29323638

MULTITASKING AND ATTENTION Emotional Life

4546

THE CASE FOR IMMEDIATE ACTION 49

THE CASE AGAINST IMMEDIATE ACTION – NON-EXISTENT Explanation of Following Sections Handling of Original Fatal Injury Information Severity Distribution in Real Life Cases Quality of Computer Simulation Part of Body Injured by Computer Simulation Severity of Injury by the Computer Simulation Controls for Computer Simulated and Real Life Injuries are Balanced Injury Costing Validity of Cost Estimates from the Abbreviated Injury scale

53535660616262646567

OVERALL SUMMARY OF SIMULATED INJURIES c/f REAL LIFE INJURIES 69

INPUT DATA REQUIRED TO ROLL THE SIMULATED QUAD BIKE 70

AN EXPLANATION OF SOME OF THE EXTRA UPPER LEG FRACTURES Spurious Result

7171

LOOKING FORWARD 73

References 74

FIGURES

1. Unscaled Time Diagram of a Personal Damaging Occurrences 22. The Analysis Reference Tree-Trunk Model © 33. Summary Taxonomy of Work Site Injuries 1980 84. Quantity of Damage to People from Work in Australia 105. Change in Temporary <6 months and Permanent in NSW 116. Change in the Quantity of Personal Damage shown in Figure 5 137. Sample of part of a Taxonomy of Class I cases from the files of Geoff

McDonald & Associates Pty Ltd15

8. Cost of Work Personal Damage in Australia 179. Percentage of Non-compensated Cases by Year and Severity 1810. Vehicle Acceleration Trailer 2411. Power Point Presentation by Robertson 2512. Performance v Arousal 3013. Response times of drivers to flashing lights and amphometers at rail

crossings31

14. Structure of the Eye 3215. Visual Acuity 3316. Peripheral, near peripheral and central vision 3417. The ‘What’ and the ‘Where’ Pathways 3518. Cathedral of San Marco, Venice 3619. Spandrel under a bridge 3720. Eiger 4921. North Face of the Eiger 5022. Quad bike set up for spraying 5023. Rider sitting erect 5024. Quad bike rolls onto erect rider 5025. Rider below upside down support structure 5126. Illustrative computer simulation printout with original injury data affixed

to the top54

27. Distribution of MAIS values 5728. DRI’s Data – Severity of Rollover Injury 6329. Injury cost line diagram 6630. Ratio of Unit Cost of Severity Levels by Year of snapshot 67

TABLES1. Percentage distribution of tractor speed and slope of terrain at the time

and point of loss of control (i.e. immediately prior to the occurrence20

2. Percentage involvement of embankments, rocks, stumps and hollows in overturing sideways occurrences

21

3. Categories of overturning sideways occurrences 224. Actual UK/US fatalities with AIS injury codes 575. Leg fractures from handlebar kickbacks in simulation 716. Comparison of leg injuries for helmeted and unhelmeted riders 72

Response to‘Review of Design and Engineering Controls

for Improving Quad Bike Safety’

This submission is outside the framework of ‘Review of Design and Engineering Controls for Improving Quad Bike Safety’, but specific answers to questions raised are given below.

Question 1.To answer this question fully requires detailed investigation of many overturning cases. Research on tractor overturnings led to the conclusion that improved stability would have only a marginal effect and that ROPS would be a more effective control measure for fatalities.

There may be some scope with quad bikes, but power/weight ratio could be relevant.

Question 2The introduction of Crush Protection Devices is the most important single initiative that could be taken.

Manufacturers have invested heavily in opposing such action and the negativity they have developed against such fitment needs to be counteracted.

The evidence they have used over many years to support their opposition is conceptually and technically unsound.

The evidence against their advocacy of training as a control measure is presented.

Retrospective fitment of CPDs is required. Footwell should also not allow the legs to be run over by the wheels.

Question 3Preventing children from starting quad bikes is a necessary but challenging requirement. It needs to be simple for an adult start but difficult for a child up to ? years of age.

Question 4The requirements for avoiding passenger carrying are valid as they were for tractors. The challenge is to overcome the ingenuity of the end users of the machines and of their friends.

If there are consistent needs for passenger carrying, a different machine e.g. a ‘side by side’, should be used.

Comments

The action being taken now to introduce Crush Protection Devices to quad bikes would have occurred 10 to 15 years ago except for the manufacturers’ active and aggressive opposition.

ii

DRI’s ‘research’ on which the manufacturers based their opposition is invalid and was demonstrably invalid from its own information.

The unnecessary loss of life from delayed adoption of Crush Protection Devices needs to be acknowledged and steps need to be taken to ensure that comparable delays do not exist elsewhere or happen again.

That this delay has happened goes to the core of Workplace Health and Safety. The influence of the invalid information should have been negated before it gained traction.

The accompanying document ‘Quad Bike Safety: In search of good theory’ gives information which helps understanding of relevant issues.

Good quality research into quad bike fatalities and permanent alteration of life, needs to bring together at least two major areas.

1. Identify the factors essential or contributing to personal damaging occurrences involving quad bikes.

2. Identify the mechanisms of damage to tissue and function of those injured

The importance of control action being based on what actually happens in the personal damaging occurrences cannot be overemphasised. The collective wisdom is likely to be distorted as it was for tractors. Sound research will give a better base for continued action for improving quad bike safety.

However, there is no reason to delay many of the innovations under consideration.

QUAD BIKE SAFETYIn Search of Good Theory

‘There is nothing so practical as a good theory’ (Kurt Lewin (1936)

It is indeed encouraging and a relief to see energetic and determined action developing to eliminate unnecessary quad bike deaths. For too long, quad bike deaths have followed the path of unnecessary tractor deaths and unnecessary 240 volt electrocutions. Sweden made Rollover Protective Structures compulsory on new tractors in 1959 and their effectiveness in reducing fatalities was established by 1964. Japan made ‘differential current operated protective devices’ (Earth Leakage Core Balance relays of ‘safety switches’) compulsory in their manufacturing industries in 1969. Their effectiveness was established by 1973. Many lives were lost by the delay in adoption in Australia of these engineering innovations.

While there were many factors involved in the delay, they revolved around the belief in human error (unsafe act) causation, a disrespect for and lack of interest in scientific and veridical (true saying) information, the use of the feeling/valuing judgement function where the thinking function was required, the use of a process which allows an individual’s position and dominance to roll over the top of sound veridical evidence, an inability to evaluate the quality of information being put forward, and lack of search for veridical information.

Judgement PairCarl Jung’s (1921) judgement functions are thinking and feeling/valuing.

The thinking function uses concepts to link up ideas into a set or organised group of ideas and to integrate new ideas into such groups. It uses the laws of reason and is essentially concerned with ‘truth’ i.e. the best fit of words and numbers to the world around us.

To understand the feeling/valuing function, take an emotion and tone it down until there is no more nervous activity than when thinking and make judgements of the form ’like or dislike' or ‘acceptable or not acceptable’. It is essentially concerned with ‘goodness’ but to goodness according to the values of the person making the judgement.

Note – this paper will cover a wide range of topics relevant to quad bike safety. Necessarily, the majority of topics will have to be dealt with briefly to limit the size of the document and to make its writing in the available time frame possible. Anything presented in this paper can be backed by substantial evidence.

2Quad Bike Safety: In Search of Good Theory

PERSONAL BACKGROUND AND ‘SHAPING’

The content of this document has been shaped by nearly two years of tractor driving, a Bachelor of Mechanical Engineering degree, a thesis only Master of Engineering degree , ‘The Involvement of Tractor Design in Accidents’, and a Bachelor of Science degree (Psychology major – most Psychology subjects studied concurrently with the Masters degree). The masters thesis identified over one hundred different design features essential to the personal damage in 520 cases resulting in 297 fatalities, 203 non-fatal injuries and a number of no injury cases. There were 204 sideways rollovers, 53 rearward overturnings and 4 overturning frontwards – 261 overtunings.

Geoff McDonald & Associates was formed in 1976 and effectively financed continuing research into workplace health and safety, sometimes on specific commissioned projects, but always continuously as a personal and professional interest.

The continuing research was directed by experience and problems presenting, but learning was strongly guided by a model, developed specifically to guide observation and investigation of ‘accidents’ (a term now rejected in favour of ‘personal damaging occurrences’. The term ‘incident’ has also been rejected because it is non-definitive.)

William Haddon’s (1963) Pre-Crash/Crash/Post Crash time diagram was expanded to 8 time zones.

Development of

Predisposing Conditions

Situation Commence

s

Metastable (control may be

regained)

Unstable (Control cannot be regained)

Damaging Energy

Exchange

Getting to Repair

Repair Stabilised

1 2 3 4 5 6 7 8(Zone 7 could usefully be divided into Medical Repair and Rehabilitation)

Figure 1. Unscaled Time Diagram of a Personal Damaging Occurrence

The Ergonomic model of Human, Machine and Environment was adopted and emphasis was placed on considering the Human/Machine, Machine/Environment and Environment/Human interactions.

A model of relevant aspects of a human being was put forward by a member of the Ergonomics Society of Australia (name unknown) prior to 1975 and was adopted and modified.

1. Metrological (size and shape)2. Information Detection3. Information Processing4. Decision Making5. Energy Giving 6. Energy Receiving7. Social8. General Adaptive

Geoff McDonald & Associates Pty Ltd September 2012


Recent research has increasingly made clear the importance of ‘attention’ and the problem of how to integrate it into this model has only recently been solved. Attention has an overall management role of Information Detection, Information Processing and Decision Making. It therefore has a very major effect on what happens. These ‘aspects’ apply equally well to the ‘Machine’ and to the ‘Environment’.

This model was to guide detection and observation of these aspects of human, of the machine and of the environment.

These separate models, Time Divisions, Ergonomic and Aspects, were combined to form the Analysis Reference Tree Trunk.

Figure 2. The Analysis Reference Tree Trunk (ART-T) Model ©

The investigative use of this model is to direct attention systematically to each of the 336 pieces of wood (7 time zones x 6 wedges x 8 aspects) in search of essential and contributory factors. What was essential that each person did do or did not do? What had to be present? What had to be absent?

All essential factors are equally important in causation (none can be elevated in importance by the term ‘cause’), but will differ in controllability. A contributory factor is not essential, but makes the damaging energy exchange more likely by making it more likely that one or more of the essential factors will be present.

The approach used follows the lead of Gibson (1961) and Haddon (1963), by seeing the distinguishing characteristic of the phenomena which safety is interested in, as one or more exchange of energy which damages tissue or function, which in turn damages the person’s life. It is ‘damage to life’ which must be the central consideration and motivation of safety. An energy exchange occurs as the climax to one or more sequences made up of essential and contributory factors.



An engineering background gave a foundation that enabled development in veridical knowledge and understanding of Size and Shape, Control Energy giving and receiving, and Damaging Energy giving and receiving.

The psychology background gave a foundation that enabled development in Information Detection, Information Processing and Decision Making and also into Social factors and General Adaptive factors which come from our evolutionary history.

The basic principles of engineering have long been established while Psychology and related fields have been developing rapidly in visual perception and information processing. Rapid advances in Neuroscience and Cognitive Psychology give a much clearer picture of the human role in personal damaging occurrences, the field of Heuristics and Biases and, more recently, Kahneman’s (2011) ‘Thinking – fast and slow’, give invaluable understanding of and insight into Decision Making. Evolutionary Biology gives an insight into human memory ‘sins’ via Daniel Schacter’s (2001) invaluable text ‘How the Mind Forgets and Remembers: the Seven sins of Memory’ in which he introduces the invaluable and necessary term ‘spandrel’ – the by-product of our evolutionary adaptation which can have a serious adverse effect on what we do and how we behave, not because we are in some way ‘bad’, but precisely because we are human. ‘Human error’ is often technically incorrect and is appropriately replaced by the term ‘spandrel’.

All of the above have provided strong motivation to use the thinking function in the search for ‘good theory’.



SCIENTIFIC METHOD AND USE OF ‘GOOD THEORY’

Scientific Method begins with Observation, Description and Classification. The initial classification is based on common features and individual differences of the phenomena which are being observed and described. There are feedback loops which sharpen the observation and description by drawing the attention away from features which have no or minimal significance and directing attention to features which have substance. Measurement can make the observations more precise, easier to communicate and facilitate comparisons with like.

As the population of case histories increases, groupings will present themselves e.g. for overturning sideways, rearwards, frontwards or for regions where control was lost on comparatively level ground, steeply sloping ground, travelling beside an embankment, contacting a sharp discontinuity in the environment.

These groupings should emerge from the data, not by requiring data to be forced into preconceived categories.

The same process applies to mechanisms of injury, parts of the body injured and severity of injury and resulting effect on a person’s life.

From the above, natural groupings can be identified and representative samples can be taken. Statistical methods are required to ensure the identified groupings are complete and reliable in the frequency of case distribution throughout the group. Representative samples can then be drawn.

At the centre of science is Hypothesis Testing. When work moves into a new area, hypotheses must be formed for various stages of the work. These hypotheses must be tested vigorously with the effort directed at rejecting the hypotheses. If it has not been possible to reject an hypothesis, the work can then be adopted with confidence. This is what leads to an increase in veridical knowledge.

The above has provided strong motivation to search for ‘good theory’ by the use of the thinking function.

Science has, over the years, developed a range of methods for increasing veridical knowledge and legitimising the use of veridical knowledge with the thinking function. Terminology, free of a feeling/valuing (affective) component, by clear and tested concepts including good theory and models, has been validated for use sometimes within prescribed limits.

Understanding of quad bike personal damaging occurrences is at an unsatisfactorily low level and there is a great need to apply scientific methods to develop veridical understanding of those personal damaging occurrences.

However, it is not acceptable to wait for better evidence before taking action because there is ‘good theory’ that can be applied,



Engineering is a professional field that applies ‘good theory’ to evaluate situations and make decisions solely as a result of application of that theory. Relevant theory for the present situation comes from Newton’s Laws of Motion which will be discussed later.

Neuroscience and Cognitive Psychology have developed in complementary ‘lock step’ to give ‘Excellent theory’ on the visual perceptual system and related information processing which involves memory and the powerful role of attention, which exists in limited quantities. Heuristics (strategies for making judgements in conditions of uncertainty) and Biases or Judgement and Decision Making (JDM) Psychologists have produced ‘good theory’ in their field.

No matter how good or excellent theory may be, its application relies on the skill of the user to know both the strengths and limitations of the theory and the need to be aware of and critically examine any assumptions made.

Two examples illustrate.

The editors of Scientific American (December 2008) wrote a one page article ‘After the Crash’, which spelt out the role of Risk Assessment in the USA financial collapse.

In 2004, the USA Securities and Exchange Commission lifted the rule for Investment Bankers to comply with ‘debt limits and capital reserves needed for a rainy day. This decision ...freed billions to invest in complex mortgage backed securities and derivatives that helped bring about the financial meltdown in September. ... The commission had freed these firms to police themselves using risk tools crafted by a cadre of quants’

The quants were physicists and mathematicians well versed in mathematics, which is as strong a form of the thinking function as exists. But the thinking judgement function was corrupted by the feeling/valuing judgements made by the economists in the financial institutions in setting the assumptions underpinning the mathematics. A subsequent enquiry found that ‘risk justification’ not risk assessment had been used. By removing the ‘debt limits and capital reserves’ requirements in return for risk assessment, the Securities and Exchange Commission, on behalf of the US government, abdicated responsibility to manage the financial institutions on behalf of the community.

A second example comes from child safety. Young children climbed into disused refrigerators, became locked inside and suffocated when the door catch latched. The first control effort, making the force required to open the door very low, failed. Subsequent filming showed that children did not struggle to get out but curled up and went to sleep. Hence the need to remove refrigerator doors from disused refrigerators.

Assumptions underlying the application of good theory are critically important.



IDENTIFYING THE GOALS FOR SAFETY

Early experience showed that as a generality, the best results come from combining experience with expertise. One, without the other, most often has limited success. Expertise, by its nature is well organised, well ordered and easy to communicate. In four years a great deal of ‘good theory’ can be communicated so graduates with high capabilities emerge. Experience, by its nature, is poorly organised, disordered, difficult to communicate and takes a long time to acquire.

Consulting started in 1976 and consisted of training specialist volunteer investigation groups in Central Queensland coal mines in the use of the ART-T model. This quickly led to ‘We can now do much better after an ART-T investigation, but why can’t you show us what to do before it happens?’ They had all been operating mainly on their individual experience and little of anything else. The response was ‘Give me your last 1000 accident reports and you will be given a taxonomy’.

Taxonomy is one of the oldest and most time honoured methods used in science. It is a classification system with an internal structure. It has its origins in Biology with its branching tree classification of the living world into Kingdom (Animalia), Class (Vertebrata), Order (Primates) Genus (Homo) Species (sapiens). It has the great advantage of presenting an overall and somewhat detailed picture in a very limited space. The idea was to present a summary and overview of past experience of the organisation so that they could produce change for the future. The taxonomy and training in the ART-T system was popular but was quickly brought to a close by the following taxonomy in 1980.

The first taxonomies had been developed from a large number of separate pieces of paper each containing a description of what happened to produce injury. The pieces of paper were sorted on the basis of common features and individual differences. Each initial pile of paper was checked for internal consistency and the rearranged piles were then further subdivided. A final check identified the basis on which the initial sorting had been done and it was found to be according to the source of the energy which took part in the final damaging energy exchange with the person.

In 1980, a company supplied 1037 pieces of paper each with a description of the personal damaging occurrence.



Figure 3. Summary Taxonomy of Worksite Injuries 1980

As seen from the taxonomy, the 1037 cases resulted in 9919 days off work. Many cases had no lost time from the injury. One case had a scheduled charge of 6000 days and another 3000 days. The company was reporting to a USA standard which required a 6000 day charge for a fatality and 3000 days for paraplegia. 2 cases cost 9000 days while the remaining 1035 cases cost 919 days. None of the 1035 cases gave any clues to predict the occurrence of the 2 cases costing 9000 days. The taxonomy was successfully predicting 10% (919 days) of the personal damage, but not the 90% (9000) days. The next two taxonomies, when the same schedule of 6000 and 3000 days was applied, gave the same result.

Note that at that time and in the present, Australian Standard AS1885.1 – 1990 ‘Workplace injury and disease recording standard’, requires a schedule charge of 200 days for a fatality and 200 days when a person is off work for over a year. This standard was not prepared by Standards Australia but by WorkSafe Australia. The taxonomies were mis-directing organisations’ efforts towards the lesser injury but numerically more frequent occurrences.

An examination of New South Wales injury statistics and those of the USA Coal Mining Industry, led to the conclusion that taxonomies were par for the course and urged for a



review of the ‘meaning’ of injuries.. What happens to a person when they are injured at work?

There are three natural divisions of the outcome. The person’s life is permanently altered, temporarily altered or insignificantly altered. These were termed Class I, Class II and Class III injuries. This raised the question of how much of the total damage to people at work falls into each Class.

A preliminaty ‘back of an envelope’ estimate showed that Class I strongly dominated on quantity of personal damage. Class I personal damage needed to be confronted directly.

Four Commonwealath Government reports have quantified the cost of work injury and disease. These four fit easily into the following classification.

Class I Permanently life altering – fatal and non-fatalClass II Temporarily life altering – recoverable lost time InjuryClass III Insignificantly life altering – medical and first aid treatment

The relative importance of these classes, based on quantity of personal damage (definitely NOT number of cases) has been quantified four times:

1992-93 Class I - 82% Fatal 1.5% Non-fatal - 80.5%2000-01 Class I - 92% Fatal 3.5% Non-fatal - 88.5% 2005-06 Class I - 91.3% Fatal 3.3% Non-fatal - 88%2008-09 Class I - 90.3% Fatal 5.3% Non-fatal - 85%1

Class I can be taken as the necessary focus for work safety and health in Australia. Currently 10 people an hour, every hour of the year, have their lives permanently altered because they went to work in Australia.

1 This percentage is reduced by a change in strategy of allocating cases to severity level. The change in strategy is open to question.



Figure 4. Quantity of Damage to People from Work in Australia

HIDDEN IN PLAIN VIEWEnergy Exchanges damage tissue and/or function which in turn damages

the person’s life permanently (Class I – Fatal; Class I – Non-fatal),temporarily (Class II – recoverable lost time injury),

insignificantly (Class III – medical and first aid treatment)

Class I Non-fatal Damage Cases Damage

1992-93 137(50,018 per year)

80.5%2000-01 134

(48,900 per year)88.5%

2005-06 175(64,000 per year)

88.0%2008-09 235

(85,800 per year)85.1%

per day365 days per year

of total cost

SNAPSHOTS OF ANNUAL PERSONAL WORK DAMAGEIN AUSTRALIA

1992-93 Industry Commission 19952000-01 National Occupational Health and Safety Commission (NOHSC) 20042005-06 Australian Safety and Compensation Council (ASCC) 20092008-09 SafeWork Australia 2012



Figure 4 has been presented starkly because of the unrecognised dominance of Class I Non-fatal personal damage.

It has long been argued that the more severe injuries are a chance worse version of the lesser injuries and safety performance can be assessed by measures such as the lost time injury frequency rate. In my experience, this has been an ‘article of faith’ rather than a validated fact. This issue was explored by McDonald (2006) by considering New South Wales WorkCover figures over 9 years from 1991-92 financial year to 2000-01 – a nine year period.

Relevant Industry ExperienceBelow are plotted Lines of Regression (line of best fit) of the Incidence of Personal damagefor 9 years of NSW experience. (Incidence cases per 1,000 work force)

The Coefficient of Determination (the percentage change due to time related factors) and theChange Rates for 10 years are presented in the two graphs of Figure 5 below.


26

TEMPORARY < 6 MONTHS

0

5

10

15

20

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

Injury Damage Line of Regression


It is impossible for the time related factors which gave a 36% decrease in ‘Temporary <6 months’ to be the same time related factors which resulted in a 140% increase in ‘Permanent’. Therefore Class II occurrence rates are not predictive of Class I occurrence rates.

Figure 5. Change in Temporary <6 months and Permanent in NSW

Note the different scales for the two diagrams. People have difficulty picturing what the comparison between ‘Temporary < 6 months’ and ‘Permanent’ means. The National Occupational Health and safety Commission (2004) gave figures which showed the ratio of costs of occurrences with less than 6 months off work to Permanent incapacity was 1 : 400.

Figure 6 shows the significance of Figure 5. The small white triangle on the left shows the decrease in personal damage with a 36% decrease in < 6 months damage and the triangle to the right shows the increase in personal damage from a 140% increase in permanent damage. This is strong evidence that the Class I Non-fatal occurrences are not a chance worse outcome of Class II occurrences.


28

0

1

2

3

4

5

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

Employment Injuries Line of Regression


Quantity of Personal Damage

Figure 6. Change in the Quantity of Personal Damage shown in Figure 5

From Figure 5 - the 1992 Incidence for <6 months is 18. - the 1992 Incidence for Permanent is 2.

From the 2000-01 and 2005-06 snapshots, if the unit cost for <6 months is 1, the unit cost of Permanent would be 100.

The plots start from 18 and 200 units respectively and finish at 11.5 and 480 units respectively.

Evidence had been given in court cases involving permanently life altering injuries in the mid 1970s. The Class I, Class II and Class III personal damage concept was in use by 1982 and was first fully presented along with estimates of relative quantity of damage in each Class in McDonald (1984).



Coming from the taxonomy which first highlighted fatality and permanent disability (Figure 3) was the motivation to find what companies needed to be told so they could focus their efforts in the most personal damage reduction effective way possible. Since the necessary information was not available, litigation cases were the only effective avenue for learning. At the present time, there are over 6,700 cases on the files of Geoff McDonald & Associates Pty Ltd. When the Industry Commission commissioned Geoff McDonald & Associates Pty Ltd to report on ‘Occupational Personal Damage Causation’ (McDonald 1995), there were 3994 cases. Figure 7 is part of the taxonomy supplied to the Industry Commission in the above report. The Industry Commission (1995) did not include the taxonomy in their report ‘Work, Health and Safety’, but endorsed the view that safety is fundamentally a Class I problem.



Figure 7. Sample of part of a taxonomy of Class I cases from the files of Geoff McDonald & Associates Pty Ltd

Of the 6,700 cases on file, McDonald has investigated and reported on 2437 personal damage cases and given evidence in many.

Those cases demanded a constant steep learning curve and confirmed the view that while some of them could be regarded as a chance worse outcome of a Class II personal damage



occurrence, the majority of them cannot. Safety should be strongly directed to controlling Class I personal damage by a knowledge of what actually happens to create such damage. Figure 4 showed that in 2008-09, there were 235 Class I non-fatal damaging occurrences per day. 10 an hour.

In the majority of litigation cases, the injured person’s lawyers have asked for a report, except in dangerous driving cases where the accused’s lawyers have asked for a report. Evidence has also been provided at the request of lawyers for the opposing parties to the above.

In the vast majority of cases, the evidence has been accepted and played a major role in the successful outcome. The evidence is drawn from identifying essential factors and applying sound engineering principles, sound ergonomic principles and sound principles in visual perception.

For completeness, a summary of the last three ‘snapshots’ of a year’s personal damage from work is given as Figure 8. The first snapshot used 6 categories of injury severity and is difficult to align with the three later snapshots.



Figure 8. COST OF WORK PERSONAL DAMAGE IN AUSTRALIA 2000-01

Workforce 9.09 millionClass II Class I TotalAbsence Incapacity Fatal

Occurrences Short<5 days

Long≥5 days

Partial Full

No. of Occurrences 186,402 114,900 22,000 26,900 2,640 352,842% of Occurrences 52.8 32.6 6.2 7.6 0.75 100

Cumulative % 52.8 85.4 91.6 99.2 100 100

COSTINGS – No allowance for pain, suffering and early deathCost of Occurrences $b 0.4 2.4 4.9 25.6 1.2 34.3

% of cost 1.2 7.0 14.3 74.0 3.5 100Cumulative % 1.2 8.2 22.5 96.5 100 100

COSTINGS – Allowance for pain, suffering and early deathCost of Occurrences $b 0. 4 2.5 21.4 53.1 5.4 82.8


2005-06Workforce 10.20 million

Class II Class I TotalAbsence Incapacity Fatal


Long≥5 days

Partial Full


Cumulative % 49.6 85.4 92.6 99.4 100 100



COSTINGS – Allowance for pain, suffering and early deathCost of Occurrences $b 0.74 4.51 45.64 83.43 8.33 142.65


2008-09Workforce 10.93 million

Class II Class I TotalAbsence Incapacity Fatal


Long≥5 days

Partial Full


Cumulative % 55.2 85.6 99.0 99.6 100 100



Pain, suffering and early death figures do not exist.


18Quad Bike Safety: In Search of Good TheoryAttention is drawn to two aspects. In the first two (2000-01 and 2005-06), the number of

‘Partial’ and ‘Full Incapacity’ cases are comparable in magnitude. In 2008-09, the vast majority of Incapacity cases were classified as ‘Partial’. A footnote includes ‘… This category (Partial Incapacity) includes permanent incapacities for which minimal duration of absence occurred and therefore the worker was able to return to working in some capacity, or for which a return to work in some capacity is possible’. (SafeWork Australia 2012, Table 1.2 Definitions and labeling of severity categories pp. 18)

This reads as if some people have not gone back to work but it is ‘possible’ that they could. Statistically, if something is possible, it has a probability between 1% and 99%. There are many factors which affect whether or not a person goes back to work. These factors influence determination of the appropriate % probability. An explanation of the factors involved and estimate of a ‘probability’ for return to work e.g. 45%, should be made and the figures adjusted accordingly.

Before becoming alarmed by an apparent deterioration in safety, examine Figure 9 ‘Percentage of Non-compensated Cases by Year and Severity’ and note how the percentage of non-compensated cases has increased with time – attributable to better survey techniques?

Figure 9. Percentage of Non-compensated Cases by Year and Severity

Category 2000-01 2005-06 2008-09 Class of Damage

Short Absence 50.0 40.0 43.0Class II

Long Absence 8.7 43.0 50.0

Partial Incapacity 8.6 47.0 56.0

Full Incapacity 8.5 43.0 51.0 Class I

Fatality 85.0 88.0 86.0

This has significance for managing the reduction of quad bike injuries. In the absence of information to the contrary, it should be assumed that quad bike injuries follow the same general pattern as other work injuries. That is, the vast majority of the quantity of damage will be Class I personal damage. The quantity of Class I non-fatal damage will probably be greater than the quantity of Class I fatal damage. This does not in any way downgrade the importance of the tragedy of fatality.

Figure 9 above makes it clear that over half of Class I non-fatal cases will not appear in compensation data. Their type of injury will remain unknown until a concerted effort is made to establish what happened. They account for over half of the largest quantity of damage.



RELEVANCE OF TRACTOR ‘ACCIDENT RESEARCH’

First of all it should be noted that tractors and quad bikes should each be treated on their own merits. They have common features and individual differences which means they are both the same and different. One similarity is their use results in rollovers which result in death. A second similarity is their use results in death from other types of occurrences. They also both produce Class I non-fatal damage.

Investigation of 520 tractor accidents, the personal investigation of 2,437 Class I personal damaging occurrences, the investigation by associates of over 4,300 cases, and work in many organizations confirm:

There will always be many essential factors in each personal damaging occurrence. The essential factors in any case will always include

o Behaviour factors -100% of the timeo Design factors -100% of the timeo Environmental factors -100% of the time

Each essential factor is equal to each of the other essential factors in causation.

Deciding any one essential factor is more important than the others and nominating it as the ‘cause’ of the occurrence and therefore the death can only be done by use of the feeling/valuing judgement function.

It cannot be done by the thinking function.

Since safety’s central concern is to prevent energy exchanges damaging a person’s tissue or function (and thereby their life), the thinking function must determine the control measures to be used.

Essential factors differ in their controllability. Controllability has many facets, but those control factors which are reliable, i.e. those which can continue to be effective without any extra input, are much to be preferred.

During the tractor fatality and injury research, not only specific design features of tractors, specific features of the environment, and specific behavior of the drivers essential to the final personal damage were learned, but much was learned around the edges. Here is some edge learning.

The aspect of tractor ‘accidents’ which fascinated and motivated interest in safety and which continues to intrigue and fascinate is that the ‘conventional wisdom’ on tractor fatalities was based on ‘Chinese whispers’. A dated ‘Chinese whisper was the message ‘Send reinforcements, we’re going to advance’, which, when passed on by a number of military mouths became ‘Send three and fourpence, we’re going to a dance.’ The message always changes to something that sits more comfortably with those transmitting and receiving the message. This extended to an ‘expert committee’ which was formed to produce a film on tractor safety.



When detailed police reports on fatalities were returned on a 7 page pro forma they had been given and which required objective information e.g. measurement of slopes (method with spirit level specified) and gear engaged, the conventional wisdom of high speeds, steep slopes and risk taking causation of rollovers was not there. Table 1 shows the percentage distribution for speed and slope of 204 sideways rollovers.

Table 1. Percentage distribution of tractor speed and slope of terrain at the time and point of loss of control (i.e. immediately prior to the occurrence)

Only 9% known to be at speed over 10 mph (16kph) with 56% under 5 mph (8kph), a slow running speed. 51.5% were on slopes under 10 degrees and only 15% known to be 20 degrees or over. Table 1 above refers to where control was lost.

In 46.5% of cases, the tractor went over an embankment (affected two wheels at the same time), 18% involved a stump, rock or hollow which affected only one wheel of the tractor. 5.5% involved both a stump etc, and an embankment and 4.5% involved a crawler tractor and an embankment. An abrupt physical feature was involved in 74.5% of cases. This made clear that the original objective of improving the sideways stability of tractors would only be marginally beneficial. Table 2 summarises the involvement of irregularities involved in the above occurrences.



Table 2. Percentage involvement of embankments, stumps, rocks & hollows in overturning sideways occurrences.

Note: Each occurrence is entered into the table only once

The behavior factors were grouped together, to give better understanding of 204 overturning sideways cases as shown in Table 3.



Table 3. Categories of overturning sideways occurrences

Note that the first 6 categories, (a) to (f), account for 56 cases and involve visual information detection which automatically involves ‘attention’ which has an overseeing role in managing ‘information detection, information processing and decision making’.

‘Lost traction; was involved in 30 cases. In the 25 embankment cases, there was insufficient information to give a clear enough picture of how or why the tractor went over the embankment. This is far from the picture which had been painted by conventional wisdom.

Quad bikes in rural industry will be operating on some of the same country, encountering some of the same features i.e. embankments, stumps, rocks, and hollows, and undertake some of the same activities (weed spraying) and presumably will also be used on more sloping and more broken country and for more difficult tasks like mustering stock.

Until detailed objective information on quad bike rollovers has been collected on significant numbers of cases, an adequate profile of rollovers will not exist to enable a valid representative sample of rollovers to be formed to attempt to apply simulations, including computer simulations. One important aspect of tractor rollovers was that the driver was doing a very familiar task that they had done in that location many times before.



MANAGING QUAD BIKE SAFETY

When consulting, companies had to agree to two requirements:

What is done to control personal damage must be firmly based on what actually happened to create the damage, and

Change for the future, not blame for the past was required,

before consulting could begin.

The dominant experience in court cases, where inspection of the workplace normally took place two, three or more years after the personal damaging occurrence, was that effective control action had not been introduced even in organizations that gave safety a high profile. The original occurrence had not been understood as companies look for ‘cause’.

First develop good quality understanding of the personal damaging occurrences, in this case those involving quad bikes, a subset of which is rollovers, which are currently subject to consideration.

There are two schools of thought being advocated.

One group, strongly supported by quad bike manufacturers, their dealers and the Federal Chamber of Automotive Industries, argue for training, behavior control and the wearing of helmets.

Another less easily defined group of Farm Safety Organisations, research groups such as those from Monash University and the University of New South Wales, Australian Centre for Agricultural Health and Safety, James Cook University, a number of interested individuals including this author, and a number of quad bike users and potential users, argue in favour of the fitment of a crush protection device, but have been thwarted by the vigorous and aggressive campaign by the quad bike manufacturers, dealers and the Federal Chamber of Automotive Industries – the first group mentioned above

This author’s involvement with quad bike rollovers began when Professor Lyn Fragar, then head of the Australian Centre for Agricultural Health and Safety and who was familiar with the tractor research, invited a group of engineers to discuss rollover structures and quad bikes. The group met in a Qantas room at Sydney airport. This was followed by a meeting convened by Yossi Berger of the AWU in Melbourne, again with engineers on the same topic. Both these groups supported the fitment of rollover protective structures.

Quite separately from these meetings, this author was asked by FarmSafe Queensland, of which he was a board member, to witness a demonstration of a quad bike with and without frame, which was mounted on an inclined ramp on a vehicle accelerator trailer, shown in Figure 10. When the quad bike rolled down the platform, it reached the bottom and rolled off and over with or without a frame. When fitted with a Robertson Quad Bar, it was held at a 90˚ roll. This was followed by an exhibition of ‘active riding’ by a skilled operator. The Quad Bar did not interfere with the active riding.



Figure 10. Vehicle Acceleration Trailer

Subsequently, again at the request of the Board of FarmSafe Queensland, a visit was made to Clifton on the Darling Downs to observe at Robertson’s premises, hydraulic load testing of the Robertson quad Bar, sideways, forwards and vertically down.

On 5th to 7th October 2010, this author was one of 6 who made up the Technical Engineering Group, called together in Sydney to consider quad bike rollover issues and ways of reducing personal damage. John Zellner of Dynamic Research, Inc. was one of the members as was Dr Shane Richardson of Delta-V Experts.

On the morning of the 5th, a number of speakers presented to the TEG group which was to report to the Heads of Workplace Health and Safety (HWSA) Trans-Tasman Working Party on quad bike safety. Robertson, in his presentation showed the following Power Point.



Figure 11. Power Point presented by Robertson

The power point had nothing on it to identify where it came from but Zellner quickly identified the figures as his.

These figures had been taken from Dynamic Research, Inc.’s (2007) report on the Robertson V-Bar and DRI (2004) report on approximate AIS injury coding of 113 US/UK accidents. Injury Severity was being rated on the Abbreviated Injury Scale from AIS 1 to AIS 6 where values mean 1 Minor, 2 Moderate, 3 Serious, 4 Severe, 5 Critical and 6 Maximum. A broken lower leg is classified as AIS 2 and a broken upper leg as AIS 3. The closest fit this scale has to Class I, Class II, Class III classification is that AIS 5 and AIS 6 could be taken as the closest equivalent to Class I Fatal and Non-fatal.

Table 1 above refers to actual injuries in the 113 case histories obtained from the UK Health & Safety Executive (59) and USA Consumer Product Safety Commission (54). Table 2 above refers to injuries from computer simulated rollovers of the 113 cases of a quad bike with no frame. These are the injuries against which the injuries from a computer simulated rollover of a quad bike fitted with a Robertson V-Bar would be compared. Increase in injury and decrease in injury would be determined and compared.

In line with the earlier argument that Class I personal damage accounts for over 90% of the total quantity of personal damage, focus on ‘Critical’ and Maximum’, real (Table 1) and simulated (Table 2).

2 real ‘heads’ have been simulated into 25 heads – 23 false predictions.

2 real chest, 1 real abdomen and 3 real asphyxiations have been simulated to zeroes – 6 false negatives

i.e. 29 false predictions and 2 correct, 93.5% false predictions.



Early on the third morning of the TEG meeting, the above argument was presented and it was argued that DRI’s ‘research’ was invalid.

The facilitator ruled that there was not time to discuss this issue as an answer was required by the end of the day. After relatively brief discussion, the path required by the facilitator was followed and Zellner was left with the task of compiling a report on the meeting with each group member able to suggest/make alterations to the report.

This author then examined the DRI (2007) report on Robertson’s V-Bar and other information from a Victorian Coronial Enquiry, and confirmed the view that the computer simulation had never been validated and that the results were invalid. Dr Shane Richardson, a fellow group member had ‘a strong background in the research, design, development, testing and introduction into service Rollover Protective Structures (ROPS). Richardson has spent the last 15 years building ROPS for vehicles as diverse as 60 tonne army tanks to 350kg quad bikes. Richardson has developed and tested more than 90 vehicles using a technique which enables the static and dynamic characteristics of the vehicle to be compared.’

McDonald and Richardson agreed that they could not communicate what was required by modifying the group document and that they should submit a minority report. An attempt made to submit a minority report was rejected, with the advice that there was no way to deal with the document and to take it elsewhere.

While the importance of the difference between Crush and Impact injuries was brought out at the meeting, the significance of this difference from Figure 11 was not spelt out. Head injuries could be either impact or crush injuries, whereas chest and abdomen and asphyxiation injuries were almost certainly crush injuries and had the potential to be controlled by a Crush Protection device (CPD).

The computer simulation had eliminated almost all trunk crush (chest, abdomen and asphyxiation) injuries and markedly amplified head injuries which could be crush or impact injuries. The results of the simulation did not indicate which. There was no scope for a crush protection device to eliminate trunk crush injuries as they had already been eliminated by the computer simulation.



TRAINING AND BEHAVIOUR CONTROL

There is no question that people should be trained to ride and do routine servicing of quad bikes so that they are able to effectively and reliably use the machine.

The evidence, that this will sufficiently and reliably reduce Class I fatal and non-fatal personal damage, or even just fatal damage, has to be produced to justify this approach.

This approach was followed with tractors with negligible effect. The belief in human error (unsafe act) causation and the following action to control and to train behaviour has been an essential factor in many deaths. When Queensland legislated for compulsory fitment of ROPS to Agricultural Tractors, one cabinet minister, John Goleby, had his industry (Horticulture) exempted from the legislation. Shortly after, he died when his tractor overturned.

When the Queensland Regional Electricity Board had their annual meeting in the late 1970s, they agreed to discourage the fitment of Earth Leakage Core Balance Relays (Safety Switches) to 240 volt systems. They decided that fitment would mean that electricians would be less diligent about following the Wiring Rules.

These are judgements made with the feeling/valuing judgement, not the thinking function as is required. They enable the fatalities to continue.

The thinking function can be and should be aided by both Neuroscience and Cognitive Psychology in a number of areas.



FACTORS WHICH AFFECT HOW, WHERE AND FOR WHAT PURPOSEA QUAD BIKE IS RIDDEN.

Factors a Quad Bike Designer Needs to Allow forAmong the complex factors which help determine how a person responds in a particular situation while riding a quad bike or how they got into the situation in the first place are arousal, attention, information detection, information processing, decision making and emotional factors.

Arousal can be thought of as the extent to which the conscious brain is active, while attention refers to where and what the brain is paying attention, including to its own thoughts. Both of these are subject to some conscious control but both are capable of doing their own thing. Neither arousal not attention has unlimited capacity.

Information Detection will be discussed in terms of visual information, but similar considerations exist for hearing, smell, hot, cold and other parts of the sensory system. Visual information is taken in through the eye which does rudimentary processing before the eye receptor signals are processed through a multitude of stations to provide ‘bottom up’ loading for the visual image being formed. ‘Top down’ loading for the image being formed and understood, comes from both short and long term memory which existed before the time of the perception.

Information Processing involves interaction of the visual image perceived (bottom upped and top downed) with experience which is partly stored in the motor response system, learned skills, and also in conscious experience in both short and long term memory. Reference is made to the work of Daniel Schacter, Chair of Psychology at Harvard University and expressed in ‘How the Mind Forget and Remembers: the Seven sins of Memory’, which introduces the important concept ‘spandrel’ an evolutionarily created characteristic which is a by-product of evolutionary adaptive features of an animal. The spandrel effects can be bland or have a powerful negative effect on the person’s behaviour. The role of attention, in both information and information processing, is discussed briefly.

Kandel (2012 pp. 284) writes ‘Attention is driven by a variety of cognitive factors, including intention, interest, previous knowledge recalled through memory, context, unconscious motivation and instinctual urges.’

Judgement or Decision Making is framed firstly in Jung’s (1921) Thinking and Feeling/Valuing judgement functions and then in terms of Heuristics (strategies for making judgements in conditions of uncertainty) and Biases (that come with each heuristic as expressed by Kahneman, Slovic and Tversky (1982). Knowledge of the Heuristics and Biases has the capacity to improve judgements but also show how judgements can go disastrously wrong./ Kahneman (2011) in his most recent work summarises 40 years of research and learning in Judgement and Decision Making (JDM) Psychology in terms of ‘Thinking, Fast and Slow’.

The fast system operates automatically and quickly with little or no effort and no sense of voluntary control. It runs the show, relies on experience which relies on affect, a subtle form of emotion defined as positive (like) and negative (dislike). It lines up roughly with Jung’s



Feeling/Valuing judgement function. Slow thinking is energy consuming and requires attention and is disrupted if attention is drawn away. Fast thinking, confronted with a difficult question which it cannot answer (and needs slow thinking to answer) will substitute a simpler question which its experience lets it answer. People generally are unaware that this process occurs within their thinking.

When the decision is made to multitask e.g. mustering and spraying weeds while using a quad bike, for 97.5% of the population, it will result in a lower standard of each task, except priority is likely to be given to the mustering and weed spraying which demand attention, leaving less attention available for riding.

Emotion has a major effect on each of us, sometimes in ways we notice and others in ways we are unaware of, in the use of the feeling/valuing judgement function and the affect in fast thinking. Neuroscientist Davidson (2012) brings together thirty years of research and describes six dimensions of Emotional Style which reflect properties of and patterns in the brain. These also need to be taken into account and allowed for.

The summary of the above and the elaboration of each that follows is that a Human Being is not some highly evolved being who, with effort and concentration, can approach perfection. We are in Gould’s (1979) words as repeated by Schacter (2001) that ‘exaptations and spandrels form a mountain to our adaptive molehill’. (Exaptations are adaptations co-opted for a different function.) We are yet to learn and appreciate ‘spandrels’ which are a by-product of evolution and which need to be allowed for in the design of machines and of work tasks.

Arousal

For present purposes, assume that when a person is asleep or in a coma, there is no level of arousal. When a person is conscious of the world around them, there is some level of arousal. (We will ignore the creative problem solving the brain can do while its owner sleeps.)

A person’s arousal level affects their performance and this is normally depicted in terms of a inverted “U” curve on a graph where the vertical axis depicts performance and the horizontal axis depicts arousal level and can also be labelled ‘anxiety’ or ‘electrical activity in the autonomic nervous system’ as shown in Figure 12.

At low levels of arousal the person’s performance level would be relatively low and as the arousal level increases the performance level increases until the optimum is reached. If the person is aroused beyond the optimum level, performance will start to drop and if arousal goes much beyond this, performance will drop very markedly. It is a skill of a coach, for example, to maintain their sports people around the optimum level of arousal so that maximum performance can be delivered and the skill of the competitor to learn to manage their arousal level to the optimum intensity.

A person’s arousal level is dependent on their internal state and on the external environment impinging upon them. A person for example who is very upset or disturbed over the state of



their life could have a very high arousal level and a person who is in a very excited state can also have a high arousal level. Where there is a wide variety of external stimuli impinging on a person and particularly where the stimuli is novel and varied, the arousal level will be high. Where stimuli is unvaried, monotonous and unchanged, the arousal level of the person will drop.

The time for which a person can maintain high arousal levels is limited and consequently there is a tendency for the human system, in the interests of efficiency, to drop the arousal level to values appropriate to the stimulus and task on hand. An excellent example of the limited time for maintaining high arousal level and consequently high performance under relatively monotonous stimuli was provided during the second world war where it was found the persons monitoring radar screens to detect incoming enemy aircraft, could only perform at the top level for periods of twenty minutes, after which time performance dropped and errors in detection occurred.

Figure 12. Performance v Arousal (anxiety, electrical activity in the autonomic nervous system (Psychology lectures late 1960s)

A good example of the influence of the environment on the arousal levels of drivers was provided by a group at Monash University who examined the response times of drivers to different stimuli and to the same stimuli set in different environmental context. They looked at the response time of drivers to flashing lights at a night rail crossing in an urban environment and two amphometers, one in an urban area and the other in an open rural area. An amphometer is a device formerly used by the Victorian police for measuring speed of motorists and consisted of two tubes laid across the road a set distance apart. The sites were selected so that the geometry of the road enabled determination of where the signal was first in the driver’s field of view. The response time was taken from the time the car passed that point until the brake lights on the car appeared.

Figure 13 shows the results of this investigation and the results can be summarised by saying that the 85th percentile response time for the night rail crossing was 1.5 seconds, for the amphometer in the urban area it was 2.5 seconds and in the rural area was 3.6 seconds. The



85th percentile is the time by which 85% of drivers have responded. The average response times were 1.15 seconds, 1.75 seconds and 2.5 seconds respectively.

Figure 13. Response times of drivers to flashing lights and amphometers at rail crossings

The difference between the night rail crossing and the amphometer in the urban area is due to the strength of the visual information being presented to the driver, whereas the difference between the amphometer in urban and rural areas represents the difference of response times as a result of different arousal levels of the motorists. Arousal levels of people driving in urban areas is generally higher than that of people driving in rural areas but the arousal level is the result of the activity the driver has to undertake in driving the vehicle (or expects to have to undertake), the amount of information which must be processed, the decision making which must occur and the manoeuvring of the car which must occur.

In taking in visual information a person does not simply regard the picture but takes in information through the eye as an active and selective process of detecting visual information.

Arousal level of quad bike riders should be expected to range from very high to very low levels. Following very high levels of arousal are inevitably lower levels and sometimes much lower levels.



Visual Perception

In order to understand visual perception, it is necessary to understand some aspects of structure and function of the eye. The eye does not simply record and transmit the available picture to the brain but has very distinctive receptor characteristics and, by moving, samples information.

Detailed visual information can only be obtained through the fovea and if reference is made to Figure 14 it can be seen that the fovea is a very small region which takes in a subtended angle of 2° coming into the eye. The reason that the fovea gives distinct vision is that it is very densely populated with visual receptors known as cones.

Figure 14. Structure of the eye

The retina of the eye is comprised of two types of receptors, rods and cones. The rods are sensitive to light, regardless of its colour, whereas the cones have distinct colour sensitivity and are responsible for colour vision. The three different types of cones are most sensitive to deep purple, green and deep red. The fovea is densely packed with cones and as you move away from the fovea, rods begin to appear in the retina and at the extremities there are only rods and no cones. Also as you move away from the fovea, the number of receptors per unit area decreases. Distinct clear vision only comes from the fovea itself which gives 2º of visual angle which corresponds to 35mm one metre in front of the eye and about 700mm at adistance of 20 metres.



Figure 15 gives an idea of the visual acuity which shows that it actually drops off very rapidly from the centre of distinct vision as you move out.

Figure 15. Visual acuity

As a result of having a small area of distinct vision, the eye must move to provide incoming information. The movement of the eye is known as saccades and the eye fixates in position for a short time and then moves rapidly to another point. On average, there are roughly two to three saccades per second, and ten percent of the time is spent with the eye actually moving. Most fixations themselves last less than half a second but the duration depends on the character of the scene and what the viewer is doing. The jumps only take a few milliseconds and vision is reduced not only during the jump but for a short time before the eye actually starts to move.

Kandel (2012) who was awarded the Nobel Prize for Physiology and medicine in 2000 for his work on memory storage in the brain, gives a relatively detailed description of the human visual perception system in ‘The Age of Insight’. He gives a valuable photograph illustrating peripheral, near peripheral and central vision. (pp. 246)



Figure 16. Peripheral, near peripheral and central vision

He then goes on to describe On centre and Off centre receptive fields. Each neuron responds only to a tiny light spot striking its receptive field.

On centre – excited by light spot on inner circle, inhibited by light spot on outer circle.Off centre – inhibited by light spot on inner circle, excited by light spot on outer circle.

The eye receptors can also detect lines and their orientation.

This shows that initial processing of visual information occurs in the eye which by the mechanism above is sensitive to contrasts.

Next come the 5 initial visual processing units V1 to V5 in the primary visual cortex.

Kandel (2012) describes the visual receptors in the retina of the eye and the initial five processing centres:

V1 organises visual information into lines, edges and corners to give contours and figure perimeters.

V2 and V3 respond to virtual lines and to borders.

V4 responds to colour, and

V5 responds to motion.

Higher regions respond to complex forms, visual scenes, specific places, hands, bodies, faces as well as to colour location in space and movement. 30 relays beyond the primary visual cortex (V1 to V5) continue analysis and segregating information about form, colour, motion and depth.

The ‘what’ visual pathway receives most of its input from the cones (colour vision) in the central region of the retina, the fovea, a relatively small area of the retina.

The ‘where’ visual pathway receives most of its input from the rods (black and white vision) in the peripheral region of the retina. It provides information necessary for guiding movement, including eye movements. The ‘where’ pathway is colour blind, and responds more quickly and is more sensitive to contrast (differences in brightness), suitable for rapid



detection of moving or dim objects. As seen in Figure 17, below, the ‘what’ and ‘where’ pathways lead to different regions of the brain. (pp. 282)

Figure 17. The ‘What’ and the ‘Where’ pathways

How are ‘what’ and ‘where’ combined? This does not occur at any single site, but occurs when the activities of the various regions of these two pathways are co-ordinated. The co-ordination is achieved by ATTENTION.

The eye can only take in detailed information from the fovea, a small area of central vision so the eye moves in 2 to 3 saccades (rapid movements) per second, and only takes in information when stationary. The eye moves as the brain requires it, to test hypotheses of what is seen.

As Kandel summarises:

‘Thus, we live in two worlds at once, and our ongoing visual experience is a dialogue between the two: the outside world that enters through the fovea and is elaborated in a ‘bottom up’ manner, and the internal world of the brain’s perceptual, cognitive and emotional models that influence information from the fovea in a ‘top down’ manner ... (emphasis added)

Attention is driven by a variety of cognitive factors including intention, interest, previous knowledge recalled through memory, context, unconscious motivation, and instinctual urges.’

In short, our visual perception is a very complex process leaving plenty of scope for what is in our vision being different from what is in our view.

As well, our visual system results in a huge range of illusions – misinterpretations of what we are looking at. These can and do create problems for the individual. Visual illusions are a specific form of spandrel.

The world has evolved in continuums and it is mankind’s wont to break it up into manageable categories. Above has been described extremely briefly, and certainly not in full complexity,



the path of visual stimuli detected by the retina through to ‘what’ and ‘where’. This is regarded as an integral part of information detection (visual perception). Perception shouldnot be regarded as having taken place until attention combines ‘what’ and ‘where’ and the fragments of information have visual meaning for us.

Information Processing

Information processing refers to the next stage where the visual perception is integrated with information in our memory, both short and long term, including our store of knowledge. It was Daniel Schacter (2001), the Chair of Harvard University’s Department of Psychology, who brought the term ‘spandrel’, introduced from architecture to evolutionary biology by Gould and Lewontin (1979), into Psychology in ‘How the Mind Forgets and Remembers: the Seven Sins of Memory’. Schacter devotes a chapter to each of the seven sins, Transience, Absent Mindedness, Blocking, Misattribution, Suggestibility, Bias and Persistence. His eighth chapter is “The Seven Sins: Vices or Virtues’.

Gould and Lewontin illustrated spandrels by referring to the space above the curves of the four arches holding up the central dome of Venice’s Cathedral of San Marco. These ‘above curve’ shapes were not wanted but are the inevitable by-product in the design.

Figure 18. Cathedral of San Marco, Venice

The space on the riverbank under a bridge can also be classified as a spandrel. The spandrel in the photograph below, a product of the river bank profile and the river’s flood height, has been effectively used as a convenient shady parking area for ‘the travelling public.’



Figure 19. Spandrel under a bridge

Schacter writes: ‘There is a difference, however, between these spandrels of memory and the architectural spandrels discussed by Gould and Lewontin. Architectural spandrels have benign consequences: they do not interfere with or undermine a building’s structural or functional integrity. Not so for memory, however. The irritation of absent-minded errors, the momentary frustration of blocking, and the potentially shattering consequences of eyewitness misidentifications and false memories resulting from misattribution or suggestibility all have the power to disrupt our lives, temporarily or permanently’.

Schacter quotes Gould as saying that exaptations and spandrels ‘... are such dominant influences in shaping the contemporary human mind that they constitute a mountain to an adaptation molehill.’ (An exaptation is an evolutionary adaptation which is co-opted for a different purpose e.g. feathers developed on small dinosaurs for thermal regulation and were later co-opted by birds for flight.)

The role of memory, both short and long term, can be illustrated by two on-farm work tasks involved in rollovers. Mustering stock and weed spraying both take the quad bike off the beaten track.

The rider may or may not be familiar with the particular paddock they are operating in, but they are most likely to have memory of comparable country and would develop, from long or short term memory a feel for the terrain – slope, general roughness, obstacles, embankments, water courses etc. The amount of grass would be variable, but climate willing, cattle and sheep will be moved before grass is grazed down too much and weeds have a habit of growing along with grass. Obstacles can be obscured.

As well as riding the quad bike, the person has to attend to the major task of mustering or spraying. When mustering, say cattle, the person will have a memory store of how cattle behave and of their body language. This is likely to be specific for general classes of animals



e.g. bulls, cows, cows with calves, calves, weaners (adolescents), and may well have memory of some specific animals. The person must anticipate and read ‘intention movements’ of individuals and groups. At times relatively quick movement may be required to stop breakaways, but there is an important line between quick action and ‘stirring up’ animals.

Attention will at times be on the animals and at other times on the terrain. When attention is on one thing, memory of the other is necessarily helping (we hope). Attention is far from being under our conscious control. Safety has an unfortunate habit of using negative judgemental terminology and it is frequently said that a person’s attention was ‘distracted’. In most cases it is ‘attracted’ as a result of our evolutionary characteristics. For example, the behaviour of one or more beasts may attract the person’s attention and hold it strongly while the quad bike rider gets the animals under control. At times, what the rider is doing will be ‘animal paced’ rather than ‘rider paced’.

Weed spraying does not have this problem. Spraying could be uniformly covering an area or ‘spot spraying’. An example of a rollover from ‘spot spraying’ will be given later. When uniformly covering an area, the visual task can be focussed on negotiating the quad bike in a set pattern of movement interrupted by topographical features as outlined with the tractors. The ground surface may be completely obscured by long grass or it could be other plants being sprayed. Blackberry spraying figured in tractor rollovers.

Regardless, terrain features can be hidden or subject to camouflage. Forbes (2009) authored ‘Dazzled and Deceived: Mimicry and Camouflage’ and gives interesting insights into and examples of both natural and military mimicry and camouflage. Sufficient here to recognise the problem exists.

Spot spraying introduces a complication that at times the weed will not be conspicuous in the surrounding grass, and while travelling, the rider will be searching for other patches of weed. In any event, during spraying, attention will be focussed on the spraying to ensure good coverage without excessive spraying.

Again the rider may have memory and experience of the paddock being sprayed and that memory may falsely reassure the person that they are operating safety. It was noted with the tractor study, that very often the driver was doing what they had done successfully many times before.

Decision Making

The study of Heuristics and Biases started in 1969 when Amos Tversky and Daniel Kahneman started working together. Heuristics are strategies for making judgements under conditions of uncertainty. Biases are the associated factors which distort those judgements. Each heuristic has its biases. Risk Assessment is a particular form (or subset) of Heuristics. Standard texts in this area include Kahneman, Slovic and Tversky (1982), ‘Judgement under Uncertainty: Heuristics and Biases’ and Slovic (2000), ‘The Perception of Risk’. These texts give great insight into how people make judgements and have particular relevance for Risk Assessment.



One of the important features of Heuristics and Biases, ignored by the USA Securities and Exchange Commission, is the fallibility of these processes.

Tversky and Kahneman (1982 pp 3) in a chapter called ‘Judgments Under Uncertainty: Heuristics and Biases’ wrote:

‘In general, these heuristics are quite useful, but sometimes lead to severe and systematic errors’

Slovic (2000), in a chapter ‘Rating the risks’ wrote:

‘Whatever role judgment plays, its products should be treated with caution. Research not only demonstrates that judgment is fallible, but it shows that the degree of fallibility is often surprisingly great and that faulty beliefs may be held with great confidence.’

Tversky and Kahneman

‘Because individuals who have different knowledge or hold different beliefs must be allowed to assign different probabilities to the same event, no single value can be correct for all people.’

Gilovich, Griffin and Kahneman (2002) in the preface wrote:

‘These heuristics typically yield accurate judgments but can give systematic error.’

There is a strong caution by all the above authors about relying on the judgements. The second quote from Tversky and Kahneman is arguing that the judgement must sit well with the beliefs and values of each individual so that they are comfortable with their judgement. While this is acceptable for some judgements, where an erring judgement can have a major effect on a person’s life, the judgement must be in line with the realities of the world.

Slovic continues further:

Slovic (2000), one of the pioneers of Heuristics and Biases, writes:‘Although risk perception was originally viewed as a form of deliberative, analytic information processing, over time we have come to recognize just how highly dependent it is upon intuition and experiential thinking, guided by emotional and affective processes. This recognition has occurred as a consequence of many streams of research.. One of these streams includes the work of a psychologist, Seymour Epstein (1994) who observed:

“There is no dearth of evidence in everyday life that people apprehend reality in two fundamentally different ways, one variously labeled intuitive, automatic, non-verbal, narrative and experiential, and the other analytical, deliberative, verbal and rational.” ‘ (pp. 710)

Slovic continues:‘One of the characteristics of the experiential system is it relies on affect. Affect is a subtle form of emotion, defined as positive (like) or negative (dislike)’ (pp xxxi)



However, the text most useful to the present considerations is by Daniel Kahneman (2011) ‘Thinking, Fast and Slow’. Kahneman, a psychologist, was awarded the Nobel Prize in

Economic Sciences in 2002. In his latest book, which summarises 40 years of research and experience, he describes two systems of thinking.

Kahneman (2011 pp. 21-23) argues for labelling the two thinking functions System 1 and System 2.

‘System 1 (fast) operates automatically and quickly with little or no effort and no sense of voluntary control.’ Examples of System 1 thinking are given below.

Detect that one object is more distant than another. Orient to the source of a sudden sound. Complete the phrase ‘bread and...’ Make a ‘disgust face’ when shown a horrible picture. Detect hostility in a voice. Answer to 2 + 2 = ? Read words on large billboards. Drive a car on an empty road. Find a strong move in chess (if you are a chess master). Understand simple sentences. Recognise that a ‘meek and tidy soul with a passion for detail’ resembles an

occupational stereotype.

‘System 2 (slow) allocates attention to the effortful mental activities that demand it, including complex computations. The operations of System 2 are often associated with the subjective experience of agency, choice and concentration.’ Examples of System 2 thinking are given below:

Brace for the starter gun in a race. Focus attention on the clowns in a circus. Focus on the voice of a particular person in a crowded and noisy room. Look for a woman with white hair. Search memory to identify a surprising sound. Maintain a faster walking speed than is normal for you. Monitor the appropriateness of your behaviour in a social situation. Count the occurrences of the letter ‘a’ in a page of text. Tell someone your phone number. Park in a narrow space (for most people except garage attendant). Compare two washing machines for overall value. Fill out a tax form. Check the validity of a complex logical argument


41Quad Bike Safety: In Search of Good TheoryThe operations of System 2 thinking required ‘...attention and are disrupted when attention is

drawn away’ (pp. 21-23) In commenting on the ‘Gorilla in the Midst’, Kahneman writes ‘The gorilla illustrates two important facts about our minds: we can be blind to the obvious,

and we are also blinded to our blindness.’ (pp. 24) (see under Multitasking and Attention for description of ‘Gorilla in the Midst’)

Kahneman describes the division of labour between the two systems:Plot Synopsis

‘The interaction of the two systems is a recurrent theme of the book, and a brief synopsis of the plot is in order. In the story I will tell, Systems 1 and 2 are both active whenever we are awake. System 1 runs automatically and System 2 is normally in a comfortable low-effort mode, in which only a fraction of its capacity is engaged. System 1 continuously generates suggestions for System 2 impressions, intuitions, intentions, and feelings. If endorsed by System 2, impressions and intuitions turn into beliefs, and impulses turn into voluntary actions. When all goes smoothly, which is most of the time, System 2 adopts the suggestions of System 1 with little or no modification. You generally believe your impressions and act on your desires and that is fine – usually.

When System 1 runs into difficulty, it calls on System 2 to support more detailed and specific processing that may solve the problem of the moment. System 2 is mobilized when a question arises for which system 1 does not offer an answer, as probably happened to you when you encountered the multiplication problem of 17 x 24. You can also feel a surge of conscious attention whenever you are surprised. System 2 is activated when an event is detected that violates the model of the world that System 1 maintains. In that world, lamps do not jump, cats do not bark, and gorillas do not cross basketball courts. The gorilla experiment demonstrates that some attention is needed for the surprising stimulus to be detected. Surprise then activates and orients your attention: you will stare, and you will search your memory for a story that makes sense of the surprising event. System 2 is also credited with the continuous monitoring of your own behaviour – the control that keeps you polite when you are angry, and alert when you are driving at night. System 2 is mobilized to increased effort when it detects an error about to be made. Remember a time when you almost blurted out an offensive remark and note how hard you worked to restore control. In summary, most of what you (your System 2) think and do originates in your System 1, but System 2 takes over when things get difficult, and it normally has the last word.

The division of labour between System 1 and System 2 is highly efficient: it minimizes effort and optimizes performance. The arrangement works well most of the time because System 1 is generally very good at what it does: its models of familiar situations are accurate, its short-term predictions are usually accurate as well, and its initial reactions to challenges are swift and generally appropriate. System 1 has biases, however, systematic errors that it is prone to make in specified circumstances. As we shall see, it sometimes answers easier questions than the one it was asked, and it has little understanding of logic and statistics. One further limitation of System 1 is that it cannot be turned off.’ (pp. 24-25)


42Quad Bike Safety: In Search of Good Theory‘Conflict between automatic reaction and an automatic reaction and an intention to control it

is common in our lives... one of the tasks of System 2 is to overcome the impulses of System 1. In other words System 2 is in charge of self control.’ (pp. 26)

In discussing cognitive illusions, illusions of thought, Kahneman writes:

‘The question that is most often asked about cognitive illusions is whether they can be overcome. The message of these examples is not encouraging. Because System 1 operates automatically and cannot be turned off at will, errors of intuitive thought are often difficult to prevent. Biases cannot always be avoided, because System 2 may have no clue to the error. Even when cues to likely errors are available, errors can be prevented only by the enhanced monitoring and effortful activity of System 2. As a way to live your life, however, continuous vigilance is not necessarily good, and it is certainly impractical. Constantly questioning our own thinking would be impossibly tedious, and System 2 is much too slow and inefficient to serve as a substitute for System 1 in making routine decisions. The best we can do is a compromise: learn to recognise situations in which mistakes are likely and try harder to avoid significant mistakes when the stakes are high. The premise of this book is that it is easier to recognise other people’s mistakes than our own.’ (pp. 28)

Kahneman indicates that System 1 is equivalent to automatic system and System 2 is equivalent to effortful system.

There is a general principle that enables prediction of people’s behaviour. They will take the least time/.least energy way of completing a task. This is seen from observations of people doing physical work and I have found it to be a consistently good predictor. Some people think it is a definition of laziness when it is actually a definition of efficiency. Not doing the task is laziness. Kahneman argues the same principle applies to mental activity.

Kahneman writes ‘The law asserts that if there are several ways of achieving the same goal, people will eventually gravitate to the least demanding course of action. In the economy of action, effort is a cost, and the acquisition of skill is driven by the balance of benefits and costs. Laziness is built deep into our nature.’ (pp. 35)

The last sentence I would argue is incorrect. What has occurred is efficiency (not laziness) in the use of effort. This means that System 1 does the work unless there is need for System 2 thinking.

Kahneman quotes Baumeister’s group as showing ‘that the idea of mental energy is more than a mere metaphor. The nervous system consumes more glucose than most other parts of the body and effortful mental activity appears to be especially expensive in the currency of glucose’. (pp. 43)

One of the fascinating concepts in this book is the idea that System 1 basically runs judgement/decision making and does so quickly and with little effort. System 1 only calls on System 2 when the task gets too difficult for System 1 and System 2 is called for. Being expensive in terms of energy (sucrose) System 2 is a reluctant starter.

Kahneman writes:


43Quad Bike Safety: In Search of Good Theory‘The main function of System 1 is to maintain and update a model of your personal world,

which represents what is normal in it. The model is constructed by associations that link ideas of circumstances, events, actions and outcomes that co-occur with some regularity, either at the same time or within a relatively short interval. As these links are formed and strengthened, the pattern of associated ideas comes to represent the structure of events in

your life, and it determines your interpretation of the present as well as your expectations of the future.’ (pp. 71)

System 2 however has ‘some ability to control the search of memory, and also to program it so that detection of an event in the environment can attract attention.’ (pp.71)

Kahneman summarises the heuristic approach: ‘These basic assessments play an important role in intuitive judgement, because they are easily substituted for more difficult questions – this is the essential idea of the heuristics and biases approach.‘ (pp.89)

Kahneman elaborates how System 1 deals with hard questions.

Substituting Questions

‘I propose a simple account of how we generate opinions on complex matters. If a satisfactory answer to a hard question is not found quickly, System 1 will find a related question that is easier and will answer it. I call the operation of answering one question in place of another substitution. I also adopt the following terms:

The target question is the assessment you intend to produce.The heuristic question is the simpler question that you answer instead.

The technical definition of ‘heuristic’ is a simple procedure that helps find adequate, though often imperfect, answers to difficult questions. The word comes from the same root as eureka.

The idea of substitution came up early in my work with Amos and it was the core of what became the heuristics and biases approach. We asked ourselves how many people managed to make judgements of probability without knowing precisely what probability is. We concluded that people must somehow simplify that impossible task, and we set out to find how they do it. Our answer was that when called upon to judge probability, people actually judge something else and believe they have judged probability. System 1 often makes this move faced with difficult target questions, if the answer to a related and easier heuristic question comes readily to mind.

Substituting one question for another can be a good strategy for solving difficult problems, and George Pólya included substitution in his classic ‘How to Solve It’: “If you can’t solve a problem, then there is an easier problem you can solve: find it.” Pólya’s heuristics are strategic procedures that are deliberately implemented by System 2. But the heuristics that I discuss in this chapter are not chosen; they are a consequence of the mental shotgun, the imprecise control we have over targeting our responses to questions.’ (pp. 97-98)


44Quad Bike Safety: In Search of Good TheoryKahneman summarises:

‘The automatic processes of the mental shotgun and intensity matching often make available one or more answers to easy questions that could be mapped onto the target question. On some occasions, substitution will occur and a heuristic answer will be endorsed by system 2. Of course, System 2 has the opportunity to reject this intuitive answer, or to modify it by incorporating other information. However, a lazy System 2 often follows the path of least effort and endorses a heuristic answer without much scrutiny of whether it is truly

appropriate. You will not be stumped, you will not have to work very hard, and you may not even notice that you did not answer the question you were asked. Furthermore, you may not realize that the target question was difficult, because an intuitive answer came readily to mind.’ (pp. 99)

Here, then, is a potential source of spandrels. System 1 substitutes an inappropriate question and develops an inappropriate answer. System 2 does not bring its considerable resources to bear on the original question, the substitute question or the answer to the substitute question. Action is taken on the basis of System 1’s answer to the inappropriate substitute question. Is this a trade-off for efficiency which enables us to cope with a very large number of questions? In time, knowledge of how the brain works will shed light on this question.

Kahneman referred earlier to cognitive illusions and stated ‘The question that is most often asked about cognitive illusions is whether they can be overcome. The message of these examples is not encouraging’. Again, like visual illusions, these cognitive illusions are a particular form of spandrel.

A problem arises when people investigate a personal damaging occurrence. They will tend to think their way through what one or more persons have done. In doing so, they are likely to be using System 2 – a slow effortful form of thinking and not appreciate that the involved people would most likely be using System 1 thinking – fast and quick, with no sense of voluntary control and may well be responding to a substitute question, a heuristic question instead of the difficult target question.

A number of widely used investigation systems use ‘tick and flick’ boxes or check lists. These run the risk of inviting the use of System 1 answering the substitute question of ‘what should I tick?’ rather than the effortful System 2 thinking to give the fullest understanding of what happened.



MULTITASKING AND ATTENTION

Many jobs require multitasking and it is often encouraged.

The downside of multitasking has long been recognised. Albert Einstein is purported to have said: ‘Any man who can drive safely while kissing a pretty girl is simply not giving the kiss the attention it deserves.’

That quotation and much of what follows is taken from David L. Strayer and Jason M. Watson’s (2012) ‘Supertaskers and the Multitasking Brain’ in the March/April issue of Scientific American Mind.

It is an overview type of article and the authors quickly make the overview very clear. Effective multitasking is a myth. Frequent multitaskers are often the worst at it. A small fraction (2.5%) of people successfully multitask. Their brain works

differently. Donald Broadbent, a pioneering Psychologist, found post World War II pilots could

take in only a limited number of signals. It is well accepted that attention is limited in capacity and can be flexibly allocated

among concurrent tasks. Devoting more attention to one task means less for another. Hands free phones and hand held phones degrade driving the same amount. Therefore cognitive distraction, not visual distraction, not manual distraction, creates

the effect. Maximum intensive focus time is 20-30 seconds. People who were high in real world multitasking had lower working memory

capacity, were more impulsive and sensation seeking, and tended to rate their own ability to multitask as higher than average. Their perceived ability and actual ability to multitask were inversely related. This work suggests that over-confidence, rather than skill, drives the proliferation of multitasking.

Many uses of quad bikes require multitasking.

One of the most famous experiments in Psychology showing the role of attention is the ‘invisible gorilla’ of ‘gorilla in the midst’. Christopher Chabris and Daniel Simons (2010) created a short film ‘of two teams of people moving around and passing basket balls. One team wore white shirts and the other wore black.’ Students then took videotapes across the Harvard campus and asked volunteers ‘to silently count the number of passes by the players wearing white while ignoring any passes by the players wearing black’. www.theinvisiblegorilla.com provides links to many of the experiments they discuss in their book, including the basketball video. ‘Watch the video carefully and be sure to include both aerial passes and bounce passes.’ The students then asked the subjects how many passes they counted and quizzed them on what they had seen.


http://www.theinvisiblegorilla.com/

46Quad Bike Safety: In Search of Good Theory‘Halfway through the video, a female student wearing a full gorilla suit walked into the

scene, stopped in the middle of the players, faced the camera, thumped her chest and then walked off, spending about nine seconds on screen.’

Roughly half the subjects in the study did not see the gorilla.

Subsequently, sports scientist Daniel Mammert of Heidelberg University ran the video using his eye tracker on the subjects watching. He found that those who failed to notice the gorilla spent the same amount of time looking right at the gorilla as did those who saw it – a full second.

The eye moves in two to three saccades per second with rapid eye movements between fixations. The direct eye sight would have been fixated on some part of the gorilla 2 to 3 times. Presumably, that image has been transmitted into visual processing. Is this a case where attention did not link up the ‘what’ and the ‘where’ to give effect to perception of the gorilla, or is there some other mechanism which gives ‘inattentional blindness’.

This author was running a course at a West Australian Iron Ore Mine. One of the 15 in the group was an attractive blonde female who had presence and was clearly liked by the group of both males and females. When she spoke they paid attention. Part way through the gorilla video, she exclaimed in a loud amazed voice ‘Gorilla!’ It was thought that she had ruined the exercise but roughly 50% of the group did not see the gorilla or hear the exclamation. It is not simply that ‘what’ and ‘where’ were not joined by attention. The auditory input and visual input of the gorilla was excluded by the visual attention focused on the ‘pass counting’ exercise.

Cognitive Psychologists Chabris and Simons’ book ‘The Invisible Gorilla’ gives a chapter about each of ‘six everyday illusions that profoundly influence our lives: the illusions of attention, memory, confidence, knowledge, cause and potential. These are distorted beliefs we hold about our minds that are not just wrong, but wrong in dangerous ways.’

The authors continue: ‘Even after we know how our beliefs and intuitions are flawed, they remain stubbornly resistant to change. We call them everyday illusions because they affect our behavior literally every day.’

Two further texts, recently published are also relevant. Macknik and Martinez-Conde with Blakeslee (2012) ‘Sleights of Mind’, was authored by Neuroscientists following a joint conference with Magicians who have a highly developed practical working knowledge of neuroscience. The book gives many aspects of attention which Magicians use to their advantage, but chapters deal with Visual, Cognitive, Multisensory, Memory and Choice Illusions as well as Illusory Correlations, Superstition, Hypnosis and Flim Flam.

Emotional Life

One aspect of human life has not yet been dealt with. Emotion. It can and does have a major effect on people’s lives and can play a part in some personal damaging occurrences. A. J. Davidson with S. Begley (2012) have written an account of thirty years’ research in affective neuroscience, which ‘has produced hundreds of findings, from brain mechanisms that


47Quad Bike Safety: In Search of Good Theoryunderlie empathy and the differences between the autistic brain and the normally developing

brain to how brains’ seat of rationality can plunge us into the toiling emotional depths of depression’.

They present the six dimensions of Emotional Style which reflect properties of and patterns in the brain.

Resilience: how slowly or quickly you recover from adversity. Outlook: how long you are able to sustain positive emotion. Social Intuition: how adept you are at picking up social signals from people around

you. Self-Awareness: how well you perceive bodily feelings that reflect emotions. Sensitivity to Context: how good you are at regulating your emotional responses to

take into account the context you find yourself in. Attention: how sharp and clear your focus is.

The emotional styles arose from systematic studies of the neural basis of emotion.

‘Each of the six dimensions has a specific, identifiable neural signature – a good indication that they are real and not merely a theoretical construct. It is conceivable that there are more than six dimensions, but it’s unlikely: The major emotion circuits in the brain are now well understood, and if we believe that the only aspects of emotion that have scientific validity are those that can be traced to events in the brain, then six dimensions completely describe Emotional Style.

Each dimension describes a continuum. Some people fall at one or the other extreme of that continuum, while others fall somewhere in the middle. The combination of where you fall on each dimension adds up to your overall Emotional Style.

Emotional Life

One aspect of human life has not yet been dealt with. Emotion. It can and does have a major effect on people’s lives and can play a part in some personal damaging occurrences. A. J. Davidson with S. Begley (2012) have written an account of thirty years’ research in affective neuroscience, which ‘has produced hundreds of findings, from brain mechanisms that underlie empathy and the differences between the autistic brain and the normally developing brain to how brains’ seat of rationality can plunge us into the toiling emotional depths of depression’.

They present the six dimensions of Emotional Style which reflect properties of and patterns in the brain.

Resilience: how slowly or quickly you recover from adversity. Outlook: how long you are able to sustain positive emotion. Social Intuition: how adept you are at picking up social signals from people around

you. Self-Awareness: how well you perceive bodily feelings that reflect emotions. Sensitivity to Context: how good you are at regulating your emotional responses to

take into account the context you find yourself in.

Attention: how sharp and clear your focus is.


48Quad Bike Safety: In Search of Good TheoryThe emotional styles arose from systematic studies of the neural basis of emotion.

‘Each of the six dimensions has a specific, identifiable neural signature – a good indication that they are real and not merely a theoretical construct. It is conceivable that there are more than six dimensions, but it’s unlikely: The major emotion circuits in the brain are now well understood, and if we believe that the only aspects of emotion that have scientific validity are those that can be traced to events in the brain, then six dimensions completely describe Emotional Style.

Each dimension describes a continuum. Some people fall at one or the other extreme of that continuum, while others fall somewhere in the middle. The combination of where you fall on each dimension adds up to your overall Emotional Style.

Everyone has elements of each of these dimensions of Emotional Style. Think of the six dimensions as ingredients in the recipe for your emotional makeup. You might have a big dollup of Focused Attentional style, a pinch of being Tuned In, and not quite as much Self-awareness as you’d like. You might have such a Positive Outlook that it overshadows everything else about you, although your lack of Resilience and Puzzlement in social situations often comes through. Who you are emotionally is the product of different amounts of each of these six components. Because there are so many ways to combine the six dimensions, there are countless Emotional styles; everyone’s in unique.’

The content of this text has not yet been assessed and digested but is included since no consideration of training and influencing people’s behavior can be anywhere complete without taking into consideration a person’s emotional characteristic – their Emotional Style – which has a strong influence on a person’s life. This is a text based on neuroscience and offers a promise of Good Theory which will inevitably result in better learning and understanding. It obviously leads to people behaving differently from each other.



THE CASE FOR IMMEDIATE ACTION

The continuing number of fatalities with quad bikes provides motivation for action. The previous section, ‘Training and Behaviour Control’ gave Good Theory on Arousal and attention managed Information Detection, Information Processing and Decision Making, which supports the practical experience that it is exceedingly difficult, indeed impossible, to develop rider behavior to achieve the necessary reduction in Class I personal damage.

This is not because of some inherent intransigence in the quad bike users, but because they are human beings, complete with their inbuilt spandrels and susceptible to a wide variety of illusions. Engineering changes are necessary.

One of the difficulties with quad bikes is that they have three different roles in our modern community – the work context, recreational use and sports/competitive use. At present, the work context is the focus of consideration.

It seems reasonable to assume that the quad bike riders in rural industries will be similar to the tractor drivers of 40 years ago. They will be better educated and in other ways different, but still the same people with the same built in characteristics. This would give rise to the proposition that the majority of fatalities, as with tractors, occur during normal every day repeated operations. This assumption should remain and be confirmed or modified by detailed investigation of occurrences.

The manufacturers may have done themselves a marketing service by calling quad bikes ‘All Terrain Vehicles’ or ‘ATVs’, but have done their users a disservice, if the user believes the ATV will live up to its name. Worse still, if the model name accentuates this impression. An example of a non-injurious rollover will be given shortly to illustrate engineering principles, but first the name.

Figure 20. Eiger

The Eiger is a mountain in the Bernese Alps in Switzerland. Its north side climbs 3,000 m above the inhabited valley and its north face, seen below, climbs 1,800 m.



Figure 21. North Face of the Eiger

Since 1935, at least 64 climbers have died in the attempt to climb the North Face of the Eiger, giving it the German nickname ‘Mordwand’ – literally ‘murder(ous) wall’. (Wikipedia)

The quad bike which overturned was set up with a spray tank on the back and a plastic crate to carry spray bottles on the front.

Figure 22. Quad bike set up for spraying

The quad bike was being used for spot spraying for rat’s tail grass mixed in with long pasture grass. Rat’s tail grass is named for the appearance of its runners and its leaves can blend with those of other grasses. While being driven across a slope, the uphill front wheel went at right angles over a small log, while the downhill front wheel went into a hollow in the ground. This was enough to roll the quad bike sideways.

Figure 23. Rider sitting erect Figure 24. Quad bike rolls onto erect rider



Figure 25. Rider below upside down support structure

Good theory was provided by Isaac Newton in his First Law which states ‘a body will remain in a state of rest, or of uniform motion in a straight line, unless compelled by an external force to change its state’.

The series of three photographs illustrate. The rider will remain predominantly in his vertical position (23) while the quad bike rolls predominantly sideways. As it does so, it will reach a state of roll which places the rider’s body roughly in the relative position shown in (24), so that when it has rolled 180˚, none of the weight of the quad bike is carried by any part of his body (25). He was fortunate that the particular roll accommodated his body in the relatively small space, which was protective of his body when the upside down quad bike was in contact with the ground. Neither the spray tank, nor the crate was damaged. The plastic spray bottles in the crate were.

The role of a Crush Protection Device is to increase the height and area, i.e. volume, of the protective space so that chance does not have to play the significant role that it did in this case, where it took the rider into the protected space.

Regardless of the speed of the tractor or quad bike, the rollover can develop very rapidly so that the person has no time to react, or even be very clearly aware of what is happening. In most cases, the rider’s attention will be directed elsewhere and the overturning must intrude to draw attention to itself. In most cases, the rider will reactively cling to the machine unless the handlebar is forced from their grip.

The notion of ease of separation from an overturning quad bike is equivalent to the belief that a young child will force their way out of a closed refrigerator, if the door opens easily. At best, separation will happen comparatively rarely. What the rider does depends on their arousal level and what their attention is doing. Field observation of acrtual injury cases is needed to provide factual information.

Car driving and travelling on a quad bike will have similar arousal problems. In open free travel situations, there is not enough stimuli input to keep the arousal level up. Attention can turn inwards to personal thoughts, coming up with a wide variety of possibilities, including decreasing arousal level. If a situation requiring action develops, response times become longer. If the arousal level goes too high, behaviour can become erratic, ranging from freezing to irrelevant action.



As the speed at rollover increases, the situation becomes less clear. At some speed, the injury problem transitions from crush to impact. By far the best insight into what happens and what is required is best determined by good quality investigation of quad bike rollovers and Class I damaging occurrences from rollovers. Some relevant evidence is available as set out by John Lambert (2010) in his Section 3.8.2 Speed and Injuries.

At the present time, available information shows that there are sufficient crush injuries to the trunk (body below the neck, minus arms and legs) and asphyxiation, to warrant the fitment of crush protection devices. These will limit some rollovers to 90˚ and provide protected space under the quad bike at a 180˚ roll.

There are finer details to be considered such as crushing of the lower leg as happens when golf buggies overturn. Again field data is required.

A crush protection device will not prevent impact injury. Current data shows a significant number of fatal head injuries and the case for wearing the most suitable (climate and impact) helmet can be considered strong. It is, at this stage, to the best of this author’s knowledge, that the role of crushing in head injuries is not sufficiently well understood.

The case for immediate action is that the engineering principle behind the function of a crush protection device is sound and evidence available on quad bike rollover fatalities provides the evidence that it will be effective. Delaying action until better quality evidence is available will result in more unnecessary deaths occurring.

Further required research will be discussed later. The problems of impact injury and excessive strain from one component of the body to another need to be better understood.



THE CASE AGAINST IMMEDIATE ACTION- NON-EXISTENT -

The quad bike manufacturers, through their representation on consultative committees, their dealers and their membership of the Federal Chamber of Automotive Industries have waged an active and aggressive campaign against the fitment of devices to prevent crush deaths from quad bike rollovers.

They argued that the fitment of these devices was ‘more likely to cause than to ameliorate harm to ATV users’. (McKellar 2009). Their argument is based on the ‘research’ of Dynamic Research, Inc. (DRI) whose major spokesperson in Australia appears to be John Zellner.

DRI’s ‘research’ is invalid, does not stand up to scrutiny, and is without merit. No decisions in relation to quad bike safety should be influenced by DRI’s work.

The ‘Research’ Was Carried Out by Dynamic Research, Inc. (DRI)

1. DRI obtained a sample of 113 quad bike rollover case histories.

2. They coded the injuries in these to the Abbreviated Injury Scale (AIS) – a six point scale.

0 No Injury, 1 Minor, 2 Moderate, 3 Serious, 4 Severe, 5 Critical, 6 Maximum

and ‘9 Unknown or Unspecified’ is used where there is insufficient information.

3. Assume the closest fit the AIS has to Class I, Class II and Class III is that AIS 5 and 6 are equivalent to Class I, fatal and non-fatal.

4. DRI developed a computer simulation programme, simulated the 113 rollovers and gave the simulated injury for each case.

5. DRI has given a summary of each of 59 rollover cases simulated. The original descriptions were supplied by the UK Health and Safety Executive (HSE). No similar summary has been seen of the 54 case histories supplied by the USA Consumer Product Safety Commission (CPSC).

6. DRI prepared a table summarising their Approximate AIS coding of the actual injuries for all 113 cases. This coding also included AIS 9 ‘Unknown or Unspecified’.

Explanation of Following Sections

Each computer simulation resulted in a single page computer printout of the results of that particular simulation. Appendix B, even run numbers, of Muñoz, Van Auken and Zellner (2007), gives the computer simulated injuries for an unhelmeted, unbelted rider on a quad bike without any frame or crush protection device.

Page 84 gives the results of Run 82200 and is used to illustrate available information.



Figure 26. Illustrative computer simulation printout with original injury data affixed to the top

To the top of the page has been affixed the Approximate AIS Injury Coding Summary of the real life injury for the occurrence being simulated. The injury was given as ‘Upper trunk fracture’ from which is has been assumed ‘2-3 ribs fractured with stable chest’ which was coded as AIS 2.

The upper part of the computer printout summarises the injuries from the computer simulation. The part of the body is given on the left and the AIS value is given in the column second from the right.



The simulated injuries in this case are: AIS

Gambit (Head) 6Face Fracture 2Neck Injury 1Upper Leg Fracture (R) 3Upper Leg Fracture (L) 3Knee Ligament Tear (R) 2Knee Ligament Tear (L) 2Lower Leg Fracture (L) 2

Injury to the upper trunk (thoracic) VC = 0Abdominal Penetration = 0

Time of Injury (or of maximum value if there is no injury) is given in the extreme right column. It is assumed, but not known, that the figure represents thousandths of a second after the computer run started.

From this printout, it can be seen that AIS 2 equates to a lower leg fracture or a knee ligament tear and AIS 3 equates to an upper leg fracture.

For the first Hypothesis, which considers how the fatalities in the original real life injuries were treated, the brief descriptions of the fatal occurrences are compared with the approximate AIS Injury Coding affixed to the top of the page. The column second from the right in Table 4, gives the page number similar to 84 of the sample page. Both the AIS coding and the ‘Coding Comments’ are used.

For the second Hypothesis, the Maximum AIS score for the original real life injury is taken from the values affixed to the top of the page.

For the third hypothesis, the part of the body described as being injured in the original injury is taken from the information affixed at the top of the page and compared with the part of body injured in the computer simulation – second column from the right, headed AIS. Parts of Body with Maximum AIS are compared.

For the fourth Hypothesis, the maximum AIS affixed to the top of the page is compared with the maximum AIS printed out by the computer.

For the fifth Hypothesis, it is assumed that most probably 4 of the 11 fatalities came from crush injuries to the trunk and looks for AIS 5 or AIS 6 for Thoracic (VC) and Abdominal Penetration – the 4th and 5th AIS levels down, and then looks for any AIS values in these positions.

The sixth hypothesis gives an overall assessment of the above hypotheses to determine the usefulness or otherwise of the simulations.

Ideally, all the pages comparable to page 84 would be supplied as a 113 page appendix so that each reader could satisfy themselves that what is said in this report is substantiated by the



appendix. Uncertainty about copyright considerations constrained the provision of such an appendix.

Handling of Original Fatal Injury Information

Van Aukin and Zellner (1996) included Annex I ‘ATV Case Summaries’ which described ‘Accidents Investigated by HSE Involving ATVs April 86-May 96’

This Annex contained the descriptions of 105 cases from which DRI selected 59 cases for simulation. It is assumed that these descriptions which came originally from the United Kingdom Health and Safety Executive (HSE) contain all the information DRI used in their simulations.

Zellner and Smith (2004) ‘Approximate AIS Injury Coding of 113 US/UK ATV Accidents’ included Appendix A ‘Approximate Injury Coding Summary’ which gives ‘Injury Descriptions’, ‘AIS Coding of Injuries’ and ‘Coding Comments’ for 113 quad bike overturning cases. This includes the 59 UK HSE cases and 54 from the USA Consumer Product Safety Commission (CPSC). No descriptions of the USA CPSC overturnings have been seen.

Hypothesis 1 DRI has made reasonable use of the information available on the 11 fatalities in the 113 UK/US quad bike rollover case histories to give their AIS coding.

DRI presented a summary of their AIS coding of the original injuries in a bar graph given below as Figure 27, taken from Zellner and Smith (2004). Note that each case is classified according to the Maximum AIS value for the injuries in that case i.e. MAIS.



Figure 27. Distribution of MAIS values (n=113)(Maximum Abbreviated Injury Scale)

The figure is read as having:

MAIS no injury 1 2 3 4 5 6 9 Number of cases 1 42 51 2 3 3 3 8

AIS 9 = unknown or unspecifiedThere are three AIS 5 and three AIS 6 cases.

Table 4 aggregates the information for the 11 fatality cases identified from the above two documents – from Annex I of the former and Appendix A of the latter.

Table 4. Actual UK/US fatalities with AIS injury codes

HSE Case Number

Actual Appendix I Page No.

AIS code

14 DP – severe head injuries (Deceased Person) 8 4, 224 Driver killed 14 631 DP – not known if from overturn or shotgun

discharge (Deceased Person) 18 9 (no injury

recorded)37 DP (Deceased person) 22 9 (no injury

recorded)42 DP Asphyxiation (Deceased Person) 26 9 (not classifiable)75 DP Asphyxiation (Deceased Person) 42 9 (not classifiable)76 Deceased – crushed 43 6

US Case Number

151 Death - asphyxiation 105 9 (not classifiable)152 Death – severe abdominal injuries 106 5153 Death - head and chest injuries, blood from

ears, neck fracture/dislocated, palpable skull fracture

107 6

159 Death - head trauma 113 4, 2



Appendix 1 to which the page number refers is not contained in this document. It refers to DRI’s computer simulation printouts of injuries without frame and without helmet. The original injuries have been affixed to each page.

Summary descriptions of UK HSE fatal case histories are given below:

The sample contained 11 fatalities. Only 3 of these were coded AIS 6. 3 asphyxiations were coded as 9 ‘Unknown or Unspecified’. 2 were coded 9 (no injury recorded). DP in the description was not recognised

as meaning Deceased Person. 2 fatal head injuries were coded AIS 4 and AIS 2 (the numbers are not

additive) 1 fatal abdominal injury was coded AIS 5.

Three UK non-fatal case histories are given below:



Note that in the document from which these were taken the fatalities were printed in bold font and in the non-fatal reports only the injuries were given in bold font.

There was nothing ‘Unknown or Unspecified” about the three Asphyxiation cases. It was known that the people were deceased and their mechanism of death, ‘asphyxiation’, was specific. The quad bike weight rested on the person long enough to drop the oxygen level in their system to fatal levels. In the coding comments for Case 42 i.e. the Approximate AIS Coding Summary (see pp. 26 Appendix I) it states ‘Asphyxia cannot be coded in AIS’. It has been coded as 9 ‘Unknown and Unspecified’. The least error coding would be to give Asphyxiation an ‘Honorary AIS 6’. That would make the maximum use of available information and improve the accuracy of Table 1.

In the two case descriptions (31 and 37 above) given ‘9 (no injury recorded)’, DP was not recognised as meaning ‘Deceased Person’, although a number of cases had IP for ‘injured person’ and Case 32 description reads:‘32 9004 (not included in the sample given above and not included in the 113 cases)DP self employed contractor travelling in ARGO-CAT ATV RH brake jammed causing violent swerve and overturn into water filled ditch. Cause of death drowning.’

This shows beyond doubt that evidence existed to show DP meant death.

In the case description copy being used for this document, the whole of the description (31 and 37 above), was in bold font – not just the injuries. These two cases should have been classified as 6.

Two cases, 24 and 76, (pp. 14 and 42), were given 6 for being killed and for being crushed to death. This was appropriate.

Case 14 was given AIS 4 and AIS 2 for ‘DP with severe head injuries’. In Coding Comments was entered:‘Assumed that head injuries were to cerebrum with a large edema with a total volume of 30-50cc with midline shift >5mm. Also assumed linear skull fracture.’

Why make an assumption? Why make an assumption in such fine detail with apparently no evidence to support it?

Case 159 was also given AIS 4 and AIS 2 for being ‘Death due to head trauma’. (pp. 113 Appendix I). This received the same injury description as Case 14 above. The same question - ‘Why?’

Case 153, despite having multiple injuries described (pp. 107 Appendix I), is given AIS 6. This is seen as appropriate but in strong contrast with the two cases given above, each given AIS 4 and AIS 2, apparently with injuries ‘assumed’ rather than from a case history report.

Why should case 152 (pp. 106) ‘severe abdominal injuries’ be given AIS 5 instead of AIS 6? There was a death.

A further case, HSE case 70 was described:



‘IP sustained extensive head injuries when ATV/OT and landed on him whilst negotiating newly made roadside embankment.’

This was given the AIS coding of 4 and 2. Coding Comments ‘Assumed that head injuries were to cerebrum with a large edema with total volume of 30-50cc with midline shift >5mm. Also assumed linear skull fracture’.

Hypothesis 1 stated DRI has made reasonable use of the information available on the 11 fatalities in the 113 UK/US quad bike rollover case histories to give their AIS coding. This hypothesis must be rejected. DRI did not make reasonable use of the information available on the 11 fatalities.

Severity Distribution of Real Life Cases

Earlier it was shown that if the concept of the natural division of personal damage (injury) is permanent alteration of life (Class I), temporary alteration of life (Class II), and insignificant alteration of life (Class III) is used, then Class I fatal and non-fatal personal damage accounts for over 90% of the total quantity of damage to people at work. AIS 6 and AIS 5 are as close as the Abbreviated Injury Scale goes to identifying Class I personal damage. This gives rise to the second hypothesis which is worded to test the suitability of the real life case histories in terms of injury severity.

Hypothesis 2. The case histories supplied by HSE (59) and CPSC (54) are sufficiently representative in severity to give reliable assessment of a crush protection device’s ability to reduce Class I damage.

There are two sets of figures - those that DRI indentified and acknowledged and those that are consistent with labelling deaths as AIS 6.

DRI’s figures can be taken from the histograms of Figure 27

MAIS no injury 1 2 3 4 5 6 9Number of cases 1 42 51 2 3 3 3 8

Of those 105 cases which DRI regarded that the injury was known and specified, 94 were of AIS 2 or less, i.e. broken lower leg or less, i.e. 94 out of 105 or 89.5%

Class II and Class III cases would be up to and including AIS 4 i.e. 99 out of 105 or 94%.

Fewer than 5.7% of cases were identified as AIS 5 and AIS 6.

It is seen as more appropriate to allocate AIS 6 to each of the fatalities. This then gives:

MAIS no injury 1 2 3 4 5 6 9Number of cases 1 42 51 2 1 2 11 3

giving 94 out of 110 cases 85.5% AIS 2 or lower, and 97 out of 110 cases 88% up to and including AIS 4. 11.8% of cases are identified as AIS 5 or AIS 6.



When the snapshots of a year’s personal damage from work were taken, 1992-03, 2000-01, 2005-06 and 2008-09, costing was only done for Class I and Class II personal damage i.e. Fatality, Full Incapacity, Partial Incapacity. Long Absence ≥ 5 days, Short Absence. They did not cost Class III – modified work, medical treatment, first aid treatment i.e. those occurrences which insignificantly alter a person’s life.

The descriptions of injuries in the AIS Injury Coding Summary (Zellner and Smith 2004) are too short to evaluate how they would affect the person in some cases. It is noted that in ‘Coding Comments’ for each case, 53 of the 113, (47%) assumptions were made about the injuries presumably to facilitate AIS coding.

Five of the CPSC cases involve nose injuries – 3 lacerations and 2 fractures. These were almost certainly Class III as are a number of other cases.

In summary 13 out of 113 cases (11.5%) are AIS 5 or AIS 6 and the vast majority of the remainder, 94 were AIS 2 (broken lower leg or less) i.e. 83%.

On this basis, Hypothesis 2, The case histories supplied by HSE (59) and CPSC (54) are sufficiently representative in severity to give reliable assessment of a crush protection device’s ability to reduce Class I damage, is rejected.

The case histories provided are not representative of the severity of the personal damaging occurrences (Class I, AIS 5 and 6) that need to be eliminated. It has been shown earlier that over 90% of the personal damage from work in Australia is from Class I fatal and non-fatal personal damage.

Quality of Computer Simulation

The computer simulations made by DRI need to be validated before its results and its use can be accepted. Validity is the extent to which something represents what it purports to represent.

DRI’s computer simulations purport to represent those quad bike rollovers which result in the personal damage we wish to eliminate.

The previous Hypothesis 2 has been rejected on the grounds that the case histories provided to them and used by them are unsuitable because of too few AIS 5 and AIS 6 injury cases.

The question now asked is if appropriate case histories were input i.e. 80-90% AIS 5 and AIS 6 quad bike rollover cases, would the computer simulation provide valid predictions? There are three aspects to this.

Does the computer simulation injure the same part of body for each case?

Does the computer simulation produce the same severity of injury for each case as existed in the real life cases?

Does the computer simulation maintain a sufficient representation of the input cases to maintain the ‘balance’ so that equitable evaluation of control measures will occur? ‘Balance’



refers to the proportion of trunk crush/asphyxiation injuries and head (impact) injuries. This should be the same for simulated injuries as for real life injuries.

Part of Body Injured by the Computer Simulation

Hypothesis 3. The simulated injuries are to the same part of the body as the real life injury.

This requires the comparison of the injuries described in Appendix A ‘Approximate Injury Coding Summary’ (Zellner and Smith 2004) with Appendix B ‘Even Numbered Runs’ (Münoz, Van Auken and Zellner 2007). The even numbered runs of Appendix B are for quad bikes with no frame and with the rider unhelmeted and unbelted i.e. the injury affixed to the top of illustrative page 84 of computer printout with the parts of body with the maximum AIS value in the computer printout.

In 103 cases, the same part of the body has not been injured i.e. in 91% of cases, the computer simulation does not predict injury to the same part of the body as occurred in real life cases. Therefore Hypothesis 3, that the simulated injuries are to the same part of the body as the real life injury, is rejected.

Severity of Injury by the Computer Simulation

Hypothesis 4. The simulated injuries are comparable in severity to real life injuries.

Figure 28 has been plotted from information on severity of real life injuries and information on severity of computer simulated injuries, disregarding the part of body injured. Assume that a difference of 1 in AIS coding is acceptable. For example, if the original real life AIS coding was AIS 1, a computer simulation injury coding of 0, 1 or 2 would be acceptable. Similarly for original AIS 2, both AIS 1 and 3 would be acceptable.



Figure 28. DRI’s DATA – SEVERITY OF ROLLOVER INJURY

Abbreviated Injury Score0 No Injury, 1 Minor, 2 Moderate, 3 Serious, 4 Severe, 5 Critical, 6 Maximum

For example, 2 = lower leg fracture, 3 = upper leg fracture9 = unknown or unspecified

Sim

ulat

ed In

jury

Sev

erity

6 16 7 7 2

5 9 4 3 1 1

4 13 5 8

3 14 1 3 4 1 1 3 1

2 33 14 13 1 1 3 1

1 16 6 8 1 1

0 12 2 9 1

Total 1 41 52 2 1 2 11 3

AIS 0 1 2 3 4 5 6 9

Real Life Injury Severity

Far too many of the UK/US cases supplied are of low severity. 94 cases had real life injuries of AIS 2 (e.g. broken lower leg) or less (83%). Only 13 cases had real life injuries of AIS 5 and 6 (11.5%).

For valid simulation, all numbers should be in the diagonal coloured boxes. (22 cases) All numbers in white boxes are, at least to some extent, invalid for severity. Only boxes vertically or horizontally removed by one place may be regarded as an acceptable severity variation (29 cases). Therefore 51 cases (just short of half) may be an acceptable level of severity. But consideration of AIS 5 and 6 gives a different story.

21 of 25 computer simulation AIS 5 and 6 came from real life AIS 0, 1 and 2.

10 of 13 real life AIS 5 and 6 gave computer simulations of AIS 3 or lower.

N.B. 103 simulations did not injure the same body part as the real life rollover.



This diagram does not represent DRI’s classification. The 8 cases they misclassified in Fatalities have been reclassified, all as real life AIS 6. This more correctly presents the input data they had, not what they showed they had.

It has been argued that the rollover sample used by DRI is unrepresentative of the Class 1 personal damage cases we wish to control.

80-90% of an acceptable sample (real life) should have resulted in AIS 5 or AIS 6 injuries. If these were well simulated, they would produce AIS 5 and AIS 6 injuries.

The red square at the top right of the figure above is the ‘gold standard’, but there are only 3 cases in the sample used by DRI. The further from the red square, the less the value of the simulation.

Of DRI’s 24 computer simulated AIS 5 and AIS 6, 21 come from computer simulation of the rollovers that produced AIS 1 or AIS 2 severity injuries. Six of the 13 real life AIS 5 and AIS 6 injuries were computer simulated as AIS 0, AIS 1, or AIS 2 and four as AIS 3.

Therefore Hypothesis 4, that simulated injuries are comparable in severity to real life injuries, has to be rejected.

Controls for Computer Simulated and Real Life Injuries are Balanced

The final question for this section is whether or not the computer simulations maintains a sufficient representation of the input cases to maintain the ‘balance’ so that equitable evaluation of control measures will occur. The major number of Class I injuries are either impact or crush. The engineering controls for each are different.

Evaluation has been done by comparing the computer simulated injuries for the quad bike with no frames and the rider wearing neither helmet not a seatbelt, with the computer simulated injuries when the only difference is the fitment of some form of crush protection device (frame).

Decrease in injuries is compared with an increase in injuries. Each injury is quantified to 6 decimal places on a 0 to 1 scale with 1 being death.

Hypothesis 5. There are sufficient cases in which the simulated injury severity is AIS 5 and AIS 6 to the trunk to test the effectiveness of a crush protective device. Trunk is understood to be the body below the neck without arms and legs.

The computer simulation printout had only two locations where an AIS coding could be given for injuries to the trunk i.e. the 4th and 5th rows under the column heading ‘AIS’. These levels correspond with ‘VC’ and ‘Abdominal Penetration’. (see Figure 26 pp. 52)

Examination of each of the 113 computer printout sheets shows that no cases score an AIS 5 or AIS 6 in the trunk positions ‘VC’ or ‘Abdominal Penetration’.

There are four scores for VC ‘thoracic’ and none for ‘abdominal penetration’. The computer printout pages for convenience have been numbers from 1 to 113.



Page No. AIS Time 12 3 0 42 1 0 76 1 1334 91 1 0

AIS 3 is equivalent to a broken upper leg. AIS 2 is equivalent to a broken lower leg.

The full range of AIS 1 is not known, but it is noted the 5 nose injuries mentioned earlier (3 lacerated and 2 broken) were all AIS 1.

Page 84 of the 113 pages of printout of computer simulations has been given as Figure 26. Note that there are 8 AIS injury ratings but 0 for the thoracic (VC) and 0 for ‘Abdominal Penetration’.

Note the original injury which has been affixed to the computer printout, with the injury described as ‘upper trunk fracture’ coded as AIS 2 and the ‘Coding Comment’ ‘Assumed 2-3 ribs fractured with stable chest’.

Note the time at which each injury occurred with it assumed for example Face Fracture occurred 4.355 seconds after the computer run started and approximately 2 seconds after the Head Injury at the top of the AIS column ‘Gambit’.

Consider the timing of the four injuries given above for VC (thoracic).

Note that three of the ‘VC’ injuries are timed at zero. If the time for page number 76 ‘VC’ injury is 1.334 seconds from the start of the computer run, the logical conclusion is that the other three occurred less than one thousandth of a second after the start of the computer run. There may be some logical explanation, but it is difficult to understand how injuries could occur at 0 time. No other injuries in the 113 cases have been noted as occurring at time 0.

Injury Costing

Halfway down the page 84 printout between the two horizontal dashed lines is

Normalised Cost of SurvivalNormalised Cost of DeathNormalised Injury Cost

Note that the 0.957655 for Normalised Injury Cost on Page 84 is the sum of Survival and Death costs. The meaning of these terms is not understood, but it is assumed that the Normalised Injury Cost is the cost of injuries in this case.

The Normalised Injury Costs for the 113 cases have been added up to 34.479 which has been rounded to 34.5. Estimates of the Normalised Injury Cost for 3 AIS 1 and 1 AIS 3 are 0.25 which is 0.72% of the total Normalised Injury Cost of 34.5.

Figure 29 is a scaled drawing of a 345mm line (total injury cost), with a 2.5mm section representing the amount of the total cost of injuries the Crush Protection Device could reduce



if it is assumed that the CPD can only prevent trunk crush injuries and asphyxiation. 2.5mm is 0.72% of 345mm.

2.5 units of cost available to be saved by Crush Protection Device after DRI’s simulation of injuries

115 potential units of fatal injury cost could be saved by CPD

345 units total injury cost

Figure 29. Injury cost line diagram

Refer back to Table 4 ‘Actual UK/US fatalities with AIS injury codes’. There are 11 fatalities including 3 asphyxiations, 1 with severe abdominal injuries and 1 crushed. There are certainly 3 probably 4 and possibly 5 deaths which could potentially be saved by a CPD, assume the 11 deaths makes up 90% of the total cost of injuries, say equivalent to 12 deaths. Assume that 4 cases have the potential for the death to be eliminated by a CPD. Then one third of the total cost of fatal injuries has the potential to be controlled by a CPD. Transferring this to the 345mm line above would give a length of 115mm which is 46 times the 2.5mm available in DRI’s simulation.

11 fatalities is, however, far too few cases to give a representative sample of fatalities.

On the basis of the above considerations, Hypothesis 5, there are sufficient cases in which the simulated injury severity is AIS 5 and AIS 6 to the trunk to test the effectiveness of a crush protective device, must be rejected.



Validity of Cost Estimates from the Abbreviated Injury Scale

The Normalised Injury Cost as seen on Figure 26 (illustrative page 84) is understood to be the basis on which increase/decrease in injury is validated.

The relative cost of an injury determines how much that type of injury influences the results. The basis on which the AIS score was developed is not known, but the ratio of their costs is incompatible with the costing ‘snapshots’ given in Figure 8 ‘Cost of Work Personal Damage in Australia’, particularly for 2000-01 where allowance was estimated for pain, suffering and early death. Pain, suffering and the consequences of early death are real and need to be allowed for.

By summing the Normalised Injury Cost in the 31 cases where there was only an AIS 2 injury, and averaging the cost, doing the same for the 12 cases where there was 0 AIS score and taking the difference, the average cost of AIS 2 was estimated as 0.0608. On the AIS costing system as used by DRI, 16.5 broken lower legs = 1 fatality.

In the vast majority of cases, a broken lower leg would be a Class II (temporary alteration of life) and fit into ‘Long Absence 5 days to <6 months’ of Figure 30 ‘Ratio of Unit Cost of Severity Levels by Year of Snapshot’.

Figure 30. Ratio of Unit Cost of Severity Levels by Year of Snapshot

Category Ratio of Cost Class of Damage

2000-01 2000-01 with pain suffering &

early death

2005-06 2008-09

Short Absence

1

4.3

1

4.5

1

4.4

1

4.2 Class IILong

Absence9.7 10.1 8.7 9.9

Partial Incapacity

103.7 453 103 190

Full Incapacity

443.5 914 422 993 Class I

Fatality 219 960 237 470

For the year 2000-01, costs including allowance for pain, suffering and early death were estimated. The cost of a Fatality to a Long Absence was 960 : 10.1. On this basis a broken lower leg is having about 6 times more influence on the costs than it should.



A broken upper leg, at AIS 3, was estimated to cost 0.186 units. This would mean 5.4 broken upper legs = 1 fatality. Where there were multiple injuries, as on page 84, (Figure 26), each injury has obviously been allocated lower values so that the sum total comes to less than 1.0.

There is an important concept, long established in communication, called Signal/Noise Ratio. Consider listening to someone in a noisy environment. As the noise level increases, so does the difficulty in hearing what the person is saying i.e. the signal. More relevant to the present consideration is if someone is trying to verbally attract your attention. Unless the signal/noise ratio is high enough, you will not hear the signal.

As argued earlier, the safety focus must be on Class I fatal and non-fatal personal damage, permanently life altering damage which accounts for over 90% of the total quantity of personal damage from work..

The Normalised Injury Cost method used by DRI is increasing the ‘noise’ which automatically decreases the ‘signal’. It does this by allocating higher costs to AIS 2 and AIS 3 than does the Australian ‘snapshots’ which include allowance for pain, suffering and early death.

This compounds with the original sample being biased to low severity injuries, with 94 out of 113 cases being AIS 2 or lower.

‘Noise’ rather than ‘signal’ could determine the outcome. Figure 29 is interesting to contemplate in terms of signal/noise ratio. For crush injuries to the trunk and for asphyxiation, the only means of evaluating a Crush Protection Device is. the 2.5 units signal, which is swamped by the 342.5 units of noise. DRI’s computer simulation was specifically to evaluate Roll Over Protective Structures (ROPS) or Crush Protection Devices (CPDs). It simply cannot do so with the signal/noise ratio it created.



OVERALL SUMMARY OF SIMULATED INJURIES c/f REAL LIFE INJURIES

1. DRI’s AIS coding of fatalities did not fit with information available.2. Trunk crush and asphyxiations AIS 5 and AIS 6 were simulated out of existence.

Only a trivial amount of trunk injury was left in three AIS 1 and one AIS 3.3. The 113 quad bike rollover cases were too low in injury severity to enable prediction

of effectiveness of Class I (AIS 5 and AIS 6) control measures 94 cases (83%) were of AIS 0, 1 or 2 severity. Only 13 cases (11.5%) were AIS 5 or AIS 6.

4. The simulations did not injure the same part of the body in 103 cases (91%) out of 113 cases.

5. In 59 cases the injury severity was two or more AIS levels different between real life and simulated injuries. 21 of 24 simulated AIS 5 and AIS 6 came from real life AIS 1 and AIS 2. Ten of the real life AIS 6 and AIS 5 were simulated into AIS 0, 1, 2 or 3.

The computer simulation is being used as a way to measure the increase of injury or decrease in injury as a result of some change made to the rider/quad bike combination. For a measure to be useful, it must be both valid and reliable to be acceptable.

Validity is the extent to which something measures what it purports to measure.

Reliability is the extent to which different people working in different places can obtain the same measures for examples of what they are measuring.

If a measure is not valid, it must be rejected regardless of its reliability as it is not measuring what is required to be measured.

This gives rise to the final hypothesis.

Hypothesis 6. DRI’s computer simulation and associated methodology provide a valid measure of both increase and decrease in Class I personal damage as measured by AIS 5 and AIS 6, as the result of fitment of a crush protection device.

In view of Hypothesis 2, Hypothesis 3, Hypothesis 4 and Hypothesis 5 being rejected, it is necessary to reject Hypothesis 6.

DRI’s simulation and methodology is invalid for the purpose described above.

Note that the classification of only three of the 11 fatalities as AIS 6, and the downgrading of the classification of the remaining 8 fatalities is not seen as having any influence on the simulated injuries. Indeed, none of the original injuries are seen as having any influence on the computer simulated injuries. In other words, it is hard to see a purpose in classifying the original injuries according to their severity as measured by the Abbreviated Injury Scale.



INPUT DATA REQUIRED TO ROLL THE SIMULATED QUAD BIKE

Any one of Hypotheses 2-6 is sufficient to reject the use of the simulation results. Hypothesis 1 should result in considerable misgiving.

A very considerable amount of work would be necessary to identify the problems in the simulation work, but one part of the process is unacceptable.

Descriptive information of the real life occurrences has only been seen for the UK HSE 59 cases and it is regarded as far from complete. Zellner of DRI agrees and has written:that ‘a minimum of 17 key variables are needed to test or simulate an overturn. The UK/US database had a minimum of 2 variables and a maximum of 17 variables and an average of 8 variables (substantially more than this for the US cases and substantially less than this for the UK cases) recorded by the UK and US government investigators for each of the 113 cases.’

The missing ‘key variables’ would have to be fabricated and entered. If only 2 of the 17 variables are known and 15 are fabricated, what is being simulated? If I were to give evidence in court and only knew the answer to 2 of the questions and fabricated the answers to the other 15 questions, my evidence would be unacceptable and should be inadmissible.

On average 8 variables were known and 9 answers were fabricated. Again, what is being simulated?

This evidence has been used in court, and on the basis of the argument used above, it should be rejected.

DRI apparently had evidence that an average of 8 out of 17 variables came with the report of the occurrence. The quality of the supplied variables information should have been validated before it was accepted.

Overall there were 17 variables entered into the computer for 113 cases, a total of 1921 variables. Roughly 900 of these are understood to have come with the descriptions of the occurrences and 1000 have been fabricated. The simulations tell more about the fabrications than the rollovers. It is not known who fabricated the missing variables, but there is clear evidence that some of it was not correct.



AN EXPLANATION OF SOME OF THE EXTRA UPPER LEG FRACTURES

In 5 cases, both with and without the V-Bar, the right upper leg is fractured in less than 0.1 seconds into the run and is the first event in the simulation. This is consistent with the leg being struck by the handlebar. In one case without a frame, the left lower leg is also broken. Table 5 shows leg fractures in simulation runs from being struck by handle bars. No such injuries, which came from a front wheel striking a large object, existed in the original UK/US sample. Note that odd run numbers are without the V-Bar and even numbers are with the V-Bar.

Table 5. Leg fractures from handle bar kickbacks in simulation

Run82---

Fracture Time (secs) Description

025 R upper leg .097 UK 23 wheel hit 21” high boulder 19kph

026 - -

027 R upper leg .094 UK 24 wheel hit 21” high obstruction 19kph028 R upper leg .078

031 L upper leg .075 UK 27 hit 36” high piece of equipment032 R & L upper leg .097, .092

073 R upper leg .081 UK 69 hit 36” high piece of equipment 38kph074 R upper leg .066

227 R upper leg .083 USA case228 R upper leg .068

The upper leg breaks are consistent with the front wheel being turned by the impact with the computer simulation of the object and forcing the handle bar back to break the leg. Since there were no such injuries there is something incorrect about the simulated object, the way it is struck by the tyre, the speed at which it is struck or the steering mechanism. Whatever the problem was, it should have been identified and corrected.

SPURIOUS RESULT

A spurious result of the simulation is that wearing/not wearing helmets altered leg injuries in 50 cases as shown in Table 6.

It has been argued that the difference in leg injury with helmet wearing/not wearing is a result of the helmet changing the person’s centre of gravity and moment of inertia. While that certainly does happen, the effects are not seen as a credible explanation. Non-human characteristics of the manikin or simulation model used are strongly suspected of being a more plausible explanation.



Table 6 below gives details of injuries in the 50 cases. In one further case, Run 203, the upper left leg fractured (unhelmeted) 2.121 seconds into the run; when helmeted, the rider’s upper leg fractured 4.496 seconds into the run, 2.375 seconds later.

Table 6. Comparison of leg injuries for helmeted and unhelmeted riders

N.B. The runs are part of series 82001 to 82304

Run No. A – Helmeted B – Unhelmeted005 0 Lower leg 2006 0 R upper leg 3 L knee 2015 0 L upper leg 3016 0 L knee 2018 R knee 2 0032 L upper leg 3 R upper leg 3 L upper leg 3044 L upper leg 3 0047 R knee 0062 R upper leg 3 0073 R upper leg 3 R upper leg 3 L lower leg 2077 0 R knee 2105 L upper leg 3 0106 L & R upper leg 3,3 L & R lower leg 2,2 0111 0 R knee 2124 R upper leg 3 0127 0 R lower leg 2130 L knee 2 0136 L & R upper leg 3,3 R lower leg 2 0138 L & R leg 3,3 0140 0 L upper leg 3148 R lower leg 2 R knee 2178 L & R upper leg 3,3 R Knee 2

L & R lower leg 2,2L & R upper leg 3,3

184 0 R knee 2 L & R knee 2,2185 0 L upper leg 3

L & R knee 2,2186 0 R lower leg 2197 L upper leg 3 L lower leg 2 0198 0 R upper leg 3 L lower leg 2 199 0 R knee 2 L lower leg 2200 R upper leg 3 R & L upper leg 3,3

R & L knee 2,2L lower leg 2

201 L knee 2 0202 L upper leg 3 R knee 2208 0 R & L upper leg 3,3212 R & L upper leg 3,3 0215 L upper leg 3 L upper leg 3 L lower leg 3230 R upper leg 3 L knee 2 0231 R knee 2 0243 L knee 2 0244 R upper leg 3 0



253 R upper leg 3 L knee 2 R & L upper leg 3,3254 R & L upper leg 3,3 R & L upper leg 3,3

R knee 2256 R & L upper leg 3,3 R & L knee 2,2

R & L lower leg 2,2R & L upper leg 3,3 R knee 2R & L lower leg 2,2

257 L lower leg 2 0259 0 R upper leg 3 R knee 2271 L upper leg 3 L knee 2

R & L lower leg 2,2R upper leg 3

272 R & L lower leg 2,2 R upper leg 3273 L upper leg 3 0277 L upper leg 3 R knee 2 L lower leg 2 L upper leg 3 R knee 2

R & L lower leg 2,2278 L upper leg 3 R knee 2 L lower leg 2 R knee 2303 R upper leg 3 R & L lower leg 2,2 R upper leg 3 R lower leg 2304 R upper leg 3 R knee 2

R & L lower leg 2,20

LOOKING FORWARD

It is hoped that the meeting on the 19 October will bring out design problems which can be overcome.

Three control problems came from the Eiger shown earlier. It was originally supplied with a ‘thumb throttle’. Thumb strike from a number of pot holes on the approach to the bridge accelerated the bike. Both rider and bike went over a drop onto the downstream waterway adjacent to the bridge. One of the collar bones was detached from its outer mounting and remains so. A corrective operation is considered too uncertain in its outcome to be justified.

Replacing the thumb throttle with a twist throttle results in a tendency to accelerate during an extreme left turn, i.e. as the handlebars are turned well to the left.

The semi-automatic transmission on a relatively new machine is variable in performance, sometimes giving smooth acceleration, sometimes rapid acceleration. On sloping country, rapid initial acceleration could help destabilise the machine.

Certainly in earlier quad bikes, there was a problem akin to the ground level access in front of the rear wheels of tractors. A rider could put their foot to the ground in front of the rear wheel and have the rear wheel climb onto the leg.

Most of the problems with tractors remained unknown or covered up until detailed reports enabled the multitude of design factors to be identified.

It is considered very important that the meeting on the 19 th October is the start of research into all forms of personal damaging occurrences with quad bikes or their replacements or alternatives, so that safer solutions can be developed effectively and efficiently based on factual information on what occurs to produce Class I personal damage.



References

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Dynamic Research Inc. (2004) Zellner J.W. and T.A. Smith. ‘Approximate AIS injury coding of 113 US/UK ATV accidents’. Report DRI-TM-04-77, Dynamic Research, Inc., December 2004.

Dynamic Research Inc. (2007) Muñoz, S., Van Auken, R.M. and J.W. Zellner. ‘An assessment of the effects of the Robertson V-Bar ROPS on the risk of rider injury due to overturns resulting from ATV misuse’. DRI-TR-07-14 Technical Report, Dynamic Research, Inc., 2007.

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Lambert, J. (2010), ‘First draft of a paper reviewing: computer simulation of ATV/quad Bike incidents as reported in various papers and presentations by Dynamic Research, Inc.; and ATV/Quad bike design and features’. John Lambert and Associates, Wandana Heights, Victoria, Australia.

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McDonald, G. L. “Better Words, Models and Concepts – Better Safety”. A paper for The Safety Conference, conducted by the Safety Institute of Australia NSW Div, Sydney, October 2006.

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