Battles with the Legion - Colin Purnell - Safety & Health Expo 2014

STARTING AT 12.30

Battles with the legion: What causes Legionnaires’ disease and how the risks can be managed

Please wear the headphones to listen to presentation

Battles with the Legion - What causes Legionnaires’ disease and how the risks can be managed.

Presented by

Dr Colin Purnell of Cogent Risk Management Ltd on behalf of the BOHS

19th June 2014

3

SETTING THE BATTLE SCENE

What are we up against?

4

Legionnaires’ Disease

• Named after an outbreak of pneumonia in people attending a convention of the American Legion at a hotel in Philadelphia in 1976

• 179 people made ill and 34 died (including passers-by)

• Causative agent eventually identified to be a previously unknown strain of bacteria, subsequently named Legionella pneumophila.

Bellevue-Stratford Hotel

5

What is Legionnaires’ diseaseLegionellosis - generic term - covers all

infections caused by legionella bacteria

Legionella bacteria cause two diseases:

Legionnaires’ disease – a rare, severe and potentially fatal form of pneumonia

Pontiac fever - mild ‘flu-like’ illness

90% of Legionnaires’ disease cases are caused by Legionella pneumophila.

6

KNOW YOUR ENEMY

7

Legionnaires’ Disease

Caused by inhaling a virulent strain of Legionella pneumophila contained in very small water droplets (aerosols)

Legionella bacteria penetrates deep into the lung (alveoli)

Legionella bacteria invade alveolar macrophages in which they reproduce in large numbers.

8

Legionnaires’ DiseaseInfection Time On-set of symptoms in 2 - 10 days,

Symptoms Fever, chill, headaches, muscular aches, dry cough, breathlessness, diarrhoea, vomiting and delirium

Incidence 250 - 350 confirmed cases a year (UK)

Mortality Rate 10 - 15% for “healthy” people, 25 - 30% for hospital patients, >50% for the immuno-suppressed

At Risk Groups 45 - 75+, alcohol drinker, smoker, (males > females) immuno-suppressed, existing

respiratory or other disease, diabetes.

9

Legionnaires’ Disease

Infective dose not known, but likely to be low,

Infection occurs mainly in people aged 50+,

Some infected persons are exposed for very short periods and/or kilometres away from the source,

Not everybody exposed develops Legionnaires’ disease.

Person to person infection believed not to occur.

10

Where are Legionella bacteria found ?In Nature• Soil, ponds, lakes and rivers.

In Man-made water systems such as:- • Hot and cold water systems and spa pools• Cooling tower water systems • Ultrasonic misting systems• Health and dental care equipment

Any water system that is capable of supporting the growth of legionella bacteria.

11

Water systems Cooling towers,

showers, spa pools, etc.

Amoebae

Biocide (if added)

Legionella in supply water,

dirt or airTemperature

20 - 46°C

Nutrients, + Iron salts, L-cysteine

Other bacteria

Sludge, scale, stagnation &

biofilms

Factors influencing the survival and growth of legionella in water systems

pH 2 - 8.5

12

How do Legionnaires’ disease outbreaks occur?

1. Legionella bacteria enters a water system,

2. Legionella bacteria are given suitable conditions to multiply to hazardous levels in the water,

3. Aerosols containing a virulent strain of Legionella bacteria are released into the air,

4. The aerosols are inhaled by susceptible persons who may then develop Legionnaires’ disease.

All the above are required to cause an outbreak of Legionnaires’ disease.

13

EXAMPLES OF BATTLES LOST

14

Headline ‘News of the World’ following outbreak Legionnaires’ disease

at Stafford District General Hospital in 1985

“KILLER CLOUD PROBEAS BUG’S TOLL REACHES 28”

175 people infected28 people died

Source of the outbreak was a cooling tower and its associated air conditioning system

Legionella bacteria entered the air of the out-patients department of the hospital.

15

How The Observer depicted Legionnaires’ disease at Stafford Hospital on 11 August 1985

16

Major Legionnaires’ Disease Outbreaks in UK since 1985

London (1988) - source - cooling tower

Corby (1997) - source - not identified

Cardiff (2000) - source - ultrasonic mister

Barrow (2002) - source - cooling tower

Hereford (2005) - source - cooling tower

Wales (2010) - source – not identified

Recent outbreaks (still under investigation)

• Edinburgh (2012) - suspected source - cooling tower

• Stoke (2012) - suspected source - spa pool.

17

HSE INVESTIGATION OF PAST OUTBREAKS

• Make someone managerially responsible for ensuring the requirements for control were properly carried out,

• Prepare a “suitable and sufficient” risk assessment,

• Implement a “robust” written scheme of precautionary measures,

• Manage their water systems properly.

The organisations involved failed to:-

18

FIGHTING THE BATTLEBY MANAGING THE RISK

19

Replaced L8 (2000)

APPROVED CODE OF PRACTICE & GUIDANCE

Revisions to L8 intended to simplify and clarify the text.

20

Removed the technical guidance from the ACOP which is now published separately as HSG274 - which has 3 parts.

Legionnaires’ disease – L8 (ACoP) 2013

MAIN CHANGE

Part 1 - Evaporative cooling systems

Part 2 - Hot & cold water systems

Part 3 - Other risk systems (includes spa pools).

21

Control of legionella bacteria in water systems

Detailed guidance on spa pools is currently provided in the 2006 HSE/PHE publication

”The Management of spa pools: Controlling the risks of infection”

Currently being updated.

22

OTHER CHANGES

risk assessment - schematic now ACoP requirement,

specific role of appointed competent "responsible" person (and requirement for deputy),

written scheme and what it should include,

regular review of risk assessment and measures,

the duties and responsibilities of those involved in the design, manufacture & supply of water systems and services (consultancy & maintenance).

The following issues now have ACOP status:

23

ACOP - SCOPE AND APPLICATION

A “reasonably foreseeable risk” of exposure to legionella bacteria exists for:-

(a) wet cooling water systems (b) hot and cold water systems (c) spa pools (d) other risk systems

All these systems require a Risk Assessment.

24

PURPOSE OF THE RISK ASSESSMENT

To enable a decision to be made on: -

the risk to health, i.e. whether the potential for harm to health from exposure is reasonably foreseeable unless adequate measures are taken,

the necessary measures to prevent, or adequately control, the risk from exposure to legionella bacteria.

25

Who should undertake the risk assessment?

• The Duty Holder under ACoP L8 can select a risk assessor – but retains responsibility for the quality of the risk assessment,

• The risk assessment must be “suitable & sufficient”,

• Must be completed by a “competent person”.

26

“Suitable and Sufficient”

all the factors pertinent to the water system’s use and operation have been considered,

an informed and valid judgement has been reached about the risks and the steps which need to be taken to achieve and maintain adequate control of legionella in the water system.

Dutyholder must be able to demonstrate that:-

27

• Primary duty is to eliminate (prevent) the risk of exposure to legionella bacteria.

• Secondary duty is to control the exposure risk by measures which do not allow proliferation of the legionella organism and reduce, SFARP, exposure of people to (inhalable) water droplets (aerosols).

ACoP - Dutyholders

28

INDG 458 - A brief guide for dutyholders

Provides information on the how dutyholders should comply with their legal duties.

29

PREVENTING OR CONTROLLING THE RISK FROM EXPOSURE TO LEGIONELLA BACTERIA

• must be prepared where the risk assessment shows that there is a reasonably foreseeable (and unavoidable) risk,

• should be properly implemented and managed,

• should specify measures to be taken to ensure that it remains effective.

THE WRITTEN SCHEME

30

THE WRITTEN SCHEME

The L8 ACoP Technical Guidance Parts 1, 2 and 3 provides detailed information of the appropriate control measures and water treatment regimes.

The written scheme must include an up-to-date schematic of the water system.

31

Arrangements in place - to ensure that the responsible person (or their appointed deputy) can be contacted at all times,

Emergency call-out procedures,

Clear lines of communication - unambiguous and regularly audited to ensure they are effective. This also applies to contractors and consultants who may be responsible for certain parts of the written scheme.

IMPLEMENTATION OF THE WRITTEN SCHEME

32

The management of the water systems involves:- a) checking the performance and operation of

the system and its component parts,

b) inspecting the “accessible” parts of the system for damage and signs of contamination,

c) monitoring to ensure that the treatment regime continues to control to the required standard.

Note: The above ACoP requirements were “guidance” in L8 (2000)

ACoP - REVIEW OF CONTROL MEASURES: MONITORING AND ROUTINE INSPECTION

33

Spa pool accessible parts

ACoP - inspect the “accessible” parts of the system for damage and signs of contamination.

34

Spa pool “inaccessible” parts !

Any “retained” risks must be considered in the written scheme pending corrective action.

35

• the responsible person(s) and their deputies,

• significant findings of the risk assessment,

• the written scheme and its implementation,

• details about the state of operation of the water system,

• results of any monitoring, inspection, tests or checks.

RECORD KEEPING

Dutyholder must ensure records are kept including:-

The L8 ACoP provides detailed guidance on exactly what records should be kept for each type of water system.

36

Review

Policy and Procedures

Water System Surveys

RiskAssessment

Written Scheme

ACoP L8 (2013) – THE WATER SYSTEM MANAGEMENT CYCLE

RemedialWorks

Audit

RECORDS

37

ROLE OF CONSULTANTS ANDWATER TREATMENT CONTRACTORS

• Water treatment programmes,

• Water hygiene services (including water sampling),

• Preparation of schematics, risk assessments and written schemes,

• Inspection, cleaning & disinfection of systems,

• Provide training

“Help and assistance” does not absolve the dutyholder from their responsibilities under ACoP L8 (2013).

38

• Must ensure the control measures are designed and implemented to be effective,

• Must provide adequate information on the correct and safe use of products in all circumstances of their use,

• Must make the dutyholder or their responsible person(s):- aware of any deficiencies in the risk assessment or

written scheme and aware of any limitations on their own expertise,

products or services.

SUPPLIERS OF PRODUCTS & SERVICES, INCLUDING CONSULTANCY & WATER TREATMENT

39

SOME FINAL COMMENTS

40

CONSEQUENCES OF AN OUTBREAK

• Adverse publicity - media, politicians, public

• Inspection of site facilities - by LA, HSE, PHE

• Criminal proceedings

• Public - nearly always affected - people die

- possible manslaughter charges

• Civil Action - award of damages

• Financial costs - management time, legal fees, fines, insurance premiums, etc.

41

Sequence Based Typing (SBT)

DNA Profiling - Sequence Based Typing (SBT) of Legionella pneumophila strains in LD patients and environmental samples now a routine investigation procedure

SBT can prove (unequivocally) that a particular strain of Legionella pneumophila bacteria in a water system was the same strain that infected the people with Legionnaires’ disease.

42

WHAT ARE THE IMPLICATIONS FOR THE DUTYHOLDER IF THINGS GO WRONG?

If the ACoP L8 (2013) provisions are not complied with then a Court of Law will view it as proof of contravention of legal requirements.

43

THE FINAL COMMENT

An outbreak of Legionnaires’ disease has never been

caused by a clean and well managed water system.

44

ANY QUESTIONS?

45

TECHNICAL GUIDANCE (HSG274) PART 1 - EVAPORATIVE COOLING SYSTEMS

Considerably expanded covering:-

• Health and Safety Law and ACoP requirements

• Types and Designs and Operation

• Requirements of cooling water system treatment

• Desired outcome in terms of water quality

• Use of biocides and alternative treatments

• Inspection, cleaning and disinfection procedures.

• Monitoring water quality and understanding reports.

46

TECHNICAL GUIDANCE (HSG274) PART 2 – HOT AND COLD WATER SYSTEMS

Considerably expanded covering:-• Health and Safety Law and ACoP requirements• Types and Application of hot and cold water systems • System design and commissioning requirements • Checklists of inspection & maintenance requirements

• Water treatment - thermal & biocides (Cl2, ClO2, etc)

• Microbiological monitoring• Cleaning and disinfection (thermal & chemical)• Managing the duty: Shared premises & landlords• Special consideration for healthcare & care homes.