Construction Health and Safety Trevor Pavitt All information contained in this presentation is confidential and the property of Alistair.

Construction Health and SafetyConstruction Health and Safety

Trevor PavittTrevor Pavitt

www.apache4change.com

All information contained in this presentation is confidential and the property of Alistair Gibb of Loughborough University.

No part of this presentation may be duplicated without the author’s specific consent.

The information presented has been shown in good faith.

Alistair Gibb, Trevor Pavitt, Katie Horne, Roger HaslamAPaCHe, Loughborough University

ISBN XXX YYY 111 000

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Occupational health is a major problem for constructionBetween 2001 and 2002 79 people died in construction and there were 3959 serious accidents. Over the same period the HSE estimates that 137 000 construction workers suffered from ill-health caused, or made worse by their job (HSE, Building, 11 July 2003).

We need to put the health back into health and safetyWork-related ill-health is under-recognised, under-reported, under-diagnosed and under-managed (Dr Andrew Colvin, medical advisor to CTRL)

Designers can make a differenceHazards are introduced at the earliest stages in a project’s life and can often be eliminated and risks reduced through the design process (CONIAC HSC/M1/02/3).

But designers often don’t know what to doHSE found that a third of designers on major construction projects demonstrated little or no understanding of their responsibilities to design-out risks (SHP June 2003).

D4h provides designers with an opportunity to make a difference to the occupational health of construction workers

Designers dangerously unaware of CDM dutiesSHP June 2003

Clients and architect ignore safetyBuilding 16 August 2002

Ill-health is like a slow-burning accidentKevin Myers, HSE Building July 2003

Vital to eliminate health hazards in designLawrence Waterman, SypolBuilding, July 2003

One in three designers ‘ignores safety’Building May 2003

Designers unaware of their duties under CDMCroner July 2003

HSE targets consultants for ignoring safe designNCE March 2003

CDM: Confusion, Despair and MayhemNCE July 2002

Designers ‘have no idea’Construction News May 2003

Designers face clamp down after safety blitzNCE May 2002

Alistair GibbRoger HaslamKatie HorneTrevor Pavitt

Alistair GibbRoger HaslamKatie HorneTrevor Pavitt

D4h – Designing for healthBest practice exemplars

D4h – Designing for healthBest practice exemplars

Recent APaCHe Projects

• ConCA – Accident Causality

• Better, easier, safer design

• ECI SHE manual• ECI Health manual.

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Current APaCHe Projects

• D4h - Designing for Healthy Construction

• HAVS - Hand-Arm Vibration study (CTRL)

• Kerbs - Manual handling (CHSG)

• CIRIA - Health Manual for Workers• HASPREST – H&S and Off-Site Production.

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D4h – Designing for Health

• Establishing best practice for designers reducing occupational health risks during construction

• Developing strategy and guidance.

Why occupational health (OH) and the need to design-out hazards are both important.

Health and Design

• OH is the poor relative of SAFETY

• TMCS Directive (CDM) requires designers to act

• OH can not be ignored – 79 fatalities in 2001-2002– 3959 serious accidents– 137 000 OH cases.

Health and Design

• Very little ‘good practice’ by designers– Only 33% had sufficient knowledge of their

duties (HSE Survey)

– Only 8% had had any training (HSE Survey)

– It has been hard to find exemplars

• But…. the supply-chain is innovating.

D4h Tool

• Provides strategic guidance for the concept design phase

• Provides element-specific guidance for the detailed design phase– Identifies main activities and health hazards– Suggests designer action to remove/reduce risk– Provides exemplars to illustrate the benefits.

D4h offers two distinct tools for designers:D4h outline strategy tool – Where the designer has the greatest opportunity to influence healthy design, but design details are not fixedD4h detailed design tool – Where healthy design is influenced by contractor and specialist input

D4h Process – Major Building

D4h Detailed Design ToolD4h Outline Design Strategy

Piling exemplar

• Many health (and safety) hazards

• Key health hazard from removal of pile top– Hand-held pneumatic breakers.

D4h Major Building – Pile top break down

• Main piling activities• Main piling health risks• Pile top break down health risks• Innovations to reduce pile top break down health risks

• Elliott pile break method• Recepieux pile break method• Taets hydraulic pile break method• Cementation-Skanska sacrificial guide wall

D4h Major Building – Pile top break down

1 2 3 4 5 6 7

Main piling activities

1 Auger fitted with appropriate head

2 Auger drilled into ground to required depth

3 Concrete poured down hollow core of auger whilst auger is removed

4 Steel reinforcement cage pushed into wet concrete

5 Wet concrete overspill at ground level removed

6 Ground level reduced and top section of pile ‘broken down’ to desired level

7 Pile cap or capping beam constructed.

D4h Major Building – Pile top break down

1 2 3 4 5 6 7

Main piling health risks

1 Manual handling aspects to changing auger heads2 Contaminated land hazards3 Dermatitis and other cement-related hazards4 Manual handling and injury risks in placing rebar cage along with cement-related

hazards5 Cement related and manual handling hazards (excess concrete typically

removed by hand)6 Major hand-arm and whole body vibration hazards (HAVS/WBVS), noise, dust

and other manual handling hazards7 Insitu concrete hazards (many and various).

D4h Major Building – Pile top break down

Main piling health risks

Survey results from Designers/Planning Supervisors (APS Aberdeen and Newcastle 9/03)Red/Yellow - High risk Black/Blue - Medium risk Blue/White – Low risk

D4h Major Building – Pile top break down

Pile top break down health risksSkin cancer from excess sun exposure

Dermatitis from cement exposure

Site Helmets

Additional safety-related issues include:Injury from exposed reinforcementUnsecured ladderStruck by machineFalls / trips on debrisPPE – eg boots, overalls, hi-visibility vestsUndermining timber hoarding

Ear protection to reduce risk from noise

Silicosis from cement dust

Eye protection to reduce risk from debris

Loughborough UniversityImage courtesy Loughborough University

This image shows a real-life construction site situationIn this case mostly poor practice

The boxes identify some of the main health hazards

Green boxes show where the site team have taken some action to reduce or control the risk

Red boxes show where they do not appear to have taken such action

In either case D4h aims to take action during design to avoid or reduce the risks before they reach site

This image was not taken from a project involving a D4h collaborator

MSDs from bad posture and restricted work area

HAVS / WBVS from breaker vibration

D4h Major Building – Pile top break down

Loughborough UniversityImages courtesy Elliott – www.Elliott-Europe.com

Occupational Health InnovationPile break method (Elliott)

Main health issues addressedHAVS and other health risks associated with breaking down of the tops of insitu bored piles

DescriptionThis technique involves the removal of the unwanted pile section in one piece, exploiting the physics of crack propagation. Steel reinforcement above the final cut-off level is prevented from bonding with the concrete by fixing isolating sleeves to the bars before the cages are lowered into position (1). When the pile is finally exposed a 51mm diameter hole is drilled horizontally into the concrete at cut-off level to just beyond the centre of the pile (2). A standard hydraulic splitter is inserted and activated (3) and after around 30 seconds the concrete cracks across the desired level. Then an excavator is used to lift off the surplus in a single piece via a lifting eye cast into the top surface (4). Elliot claim that the operation cuts the hand-arm vibration risk by more than 90%. It will work on pile diameters from 300mm to 3m and typically takes around 10 minutes (5), bringing significant productivity and cost benefits.

Design action requiredActual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer).

Main residual health risksOne 51mm hole is drilled into the pile with some associated vibration hazards (approx 5 minutes task time). Some MSD hazards may remain in the manoeuvring of the pile top section although this is a crane operation.

Note: There are a number of alternative methods addressing this health risk. (link to table)

1

2

3

4

5

Elliott Crack PropagationElliott Crack Propagation

Courtesy Elliott

D4h Major Building – Pile top break down

Loughborough University Images courtesy Recepieux – (http://www.recepieux.com)

Occupational Health InnovationChemical pile break method (Recepieux)

Main health issues addressedHAVS and other health risks associated with breaking down of the tops of insitu bored piles

DescriptionRecepieux’s technique involves the removal of the unwanted pile section in one piece, exploiting the principle of crack propagation induced using an expanding grout. The steps are as follows:1 Foam sleeves are fixed over the reinforcement over the length to be removed2 A series of PVC tubes and cones is assembled3 The tube and cone assembly is pushed into the wet concrete4 The tube assembly is checked for level and funnels fixed to the top of the tubes5 The temperature of the pile concrete is measured (this affects the grout mix choice)6 The expanding grout is mixed and batched into containers7 The grout is poured into the tubes via the funnels8 The grout expands in the cones set at ‘cut-off’ level propagating a horizontal crack through the pile9 The top unwanted section is removed by crane

Design action requiredActual choice of technique is usually left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer).

Main residual health risksCOSHH issues with the grout and increased work required to the wet concrete during pile construction. Some MSD hazards may remain in the maneuvering of the pile top section.

Note: There are a number of alternative methods addressing this health risk. (link to table)

1 2

3

5

6

8 9

7

4

Note: there are examples of poor use of PPE in these images

• Traditional insitu bored pile cast approximately 1m above cut-off level

• Horizontal crack induced at cut-off level by expanding grout inserted through tubes.

Recepieux Chemical Crack propagationRecepieux Chemical Crack propagation

Courtesy Recepieux

Courtesy Recepieux

Note poor PPE

Recepieux Chemical Crack propagationRecepieux Chemical Crack propagation

D4h Major Building – Pile top break down

Loughborough UniversityImages courtesy Taets – (http://www.taets.nl/#B)

Occupational Health InnovationHydraulic pile break method (Taets)

Main health issues addressedHAVS and other health risks associated with breaking down of the tops of insitu bored piles

DescriptionThe Taets system from the Netherlands replaces hand-held pneumatic breaking with a large scale hydraulic breaker. The breaker is suspended from an excavator and makes a horizontal fracture in the pile at cut-off level. Each hydraulic cylinder drives a chisel into the concrete producing a horizontal fracture as the breaking force built up this way always seeks the shortest way through the concrete. This stage takes about 25 seconds. The steel chisels do not have to penetrate beyond the reinforcement bars. After the fracture is made, the chisels penetrate further into the concrete (usually 25-40 mm). Due to the shape of the chisel, in combination with the reaction forces on the concrete by the steel reinforcement, the concrete breaks into pieces and can removed without the need for further breaking.

Design action requiredActual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer).

Main residual health risksSlight MSD risk maneuvering breaker although this is a crane / excavator operation. MSD risks disposing of broken concrete – depending on techniques used. Some dust and noise.

Note: There are a number of alternative methods addressing this health risk. (link to table)

D4h Major Building – Pile top break down

Loughborough UniversityImages courtesy Taets – (http://www.taets.nl/#B)

D4h Major Building – Pile top break down

Loughborough UniversityImage courtesy Mantovanibenne

Occupational Health InnovationHydraulic pile break method (Mantovanibenne )

Main health issues addressedHAVS and other health risks associated with breaking down of the tops of insitu bored piles

DescriptionThe Mantovanibenne system replaces hand-held pneumatic breaking with a large scale hydraulic breaker in a similar way to the Taets system. This system was recently used on Norwich FC’s Carrow Road ground (NTW Civil Engineering / Inmalo). The system can accommodate piles between 350 and 1600mm for both circular and square piles. The team claim significant productivity as well as health and safety benefits (Construction News, 11/09/03 p.20).

Design action requiredActual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer).

Main residual health risksSlight MSD risk maneuvering breaker although this is a crane / excavator operation. MSD risks disposing of broken concrete – depending on techniques used. Some dust and noise.

Note: There are a number of alternative methods addressing this health risk. (link to table)

D4h Major Building – Pile top break down

Loughborough UniversityCourtesy Mantovanibenne

• Traditional insitu bored pile cast approximately 1m above cut-off level

• Hand-held breaking replaced by crane-handled hydraulic breaker.

Option 4 – Hydraulic breakerOption 4 – Hydraulic breaker

Courtesy Taets

D4h Major Building – Pile top break down

Occupational Health InnovationPrecast sacrificial guide wall (Cementation-Skanska)

Main health issues addressedHAVS and other health risks associated with breaking down of the tops of insitu bored piles, along with other pile top hazards

DescriptionContiguous piled walls require more accurate alignment and need a temporary, sacrificial concrete guide wall to be cast before the piling operations through which the auger passes. The Cementation-Skanska system prevents the abortive work of the early guide wall, which in the final permanent state is usually replaced by a concrete capping beam of similar dimensional proportions. The system utilizes pre-cast concrete guides placed into position and retained by a non-structural concrete surround. By preventing contamination to the tops of the piles, they can be poured to ‘cut-off’ level in the first place removing the need to break-down the pile tops. Circular voids in the mould allow the piling auger to pass through the mould in the required position. Adjacent voids are protected with circular ‘lids’ to prevent them being filled with concrete or pile arisings. 1 - guide blocks being placed along the line of the wall2 - auger drilling ‘through’ the block guides 3 - blocks removed after the piling operation and also the shape left by the blocks acting as the formwork for the capping beam.

Design action requiredActual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer).

Main residual health risksAdditional operations involve the placement of the precast guide wall units which may involve some MSD hazards.

Note: There are a number of alternative methods addressing this health risk. (link) Loughborough UniversityImages courtesy Cementation Foundations - Skanska

• Designed for contiguous piling

• Enables pile to be cast to ‘cut-off’ level

• Avoids contamination of wet concrete from surrounding ground

• Avoids need for breaking down pile top.

Cementation-Skanska sacrificial guide wall

Cementation-Skanska sacrificial guide wall

Courtesy Cementation-Skanska and Carillion

D4h Major Building – Pile top break down

Loughborough University

Innovations to reduce health risk

Method Health hazards reduced / removed Residual health hazards

Elliott crack method

‘Manual’ removal of pile top is avoided by the crack splitter resulting in a large concrete section removed by crane

51mm hole drilled into the pile with some associated vibration hazards.

Some MSD hazards may remain in the manoeuvring of the pile top section.

Recepieux chemical method

‘Manual’ removal of pile top is avoided by the chemical technique resulting in a large concrete section removed by crane

COSHH issues with the grout.

Increased work required to the wet concrete during pile construction.

Some MSD hazards may remain in the manoeuvring of the pile top section.

Taets hydraulic breaker

‘Manual’ removal of pile top is replaced by a crane-handled hydraulic machine

Some MSD hazards may remain in the manoeuvring of the hydraulic breaker and in the ultimate removal of the broken concrete.

Cementation sacrificial guide wall (contiguous piling)

The need for over-pouring of the concrete pile is removed as the pile is poured to the correct cut-off level, protected from contamination of the surrounding ground by the precast guide wall.

Additional operations involve the placement of the precast guide wall units which may involve some MSD hazards.

Designer/PS knowledge of pile break innovations

Have used it

Know it w ell

Have heard of it

Never heard of it

Sacrif icial guide w all - Cementation-Skanska 0 0 15 25Hydraulic pile splitter - Elliott 3 1 16 20Chemical pile break - Recepieux 0 0 6 34Crane-handled hydraulic break - Taets 2 1 12 25

Sample size 40

Main primary function – designers (Arch & Eng)

Main secondary function – Planning Supervisors

D4h Designing for healthy construction

The challenge…….. To design-out health risks for construction workers

• Are we aware of the innovations?• Do our designs preclude their use?• Do we have mechanisms in place to access

expert knowledge?• Are we proactive in encouraging design

innovations?.

There is a better way!Construction Health and SafetyConstruction Health and Safety

Alistair GibbAlistair Gibb