Legionella Risk Assessment
Mike Rose
Legionella Risk Assessment
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Identification and evaluation of sources of potential risk
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Means by which exposure is to be prevented
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Means by which exposure is to be controlled
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Fundamental to the development of an effective management
system
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Must be suitable and sufficient
What constitutes suitable and sufficient?
Legionella Risk Assessment
Legionnaires’ disease The control of legionella bacteria in water
systems ACoP and Guidance (L8)
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Very limited in detail relating to risk assessment content
No clear level of expectation for clients
Variability in risk assessment quality
Increased risk of Legionnaires’ disease
Outbreaks of Legionnaires’ disease are often associated with
inadequate risk assessment
BS 8580:2010 Code of Practice
BS 8580:2010 Water quality - Risk Assessment for Legionella
Control, Code of Practice
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Factors to be considered in the risk assessment
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Contamination
Amplification
Transmission
Exposure
Host Susceptibility
Preparations for risk assessment
– Competence of risk assessor
– Agreeing terms of reference
– Independence.
BS 8580:2010 Code of Practice
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Desktop appraisal of documentation
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Previous risk assessment
Current scheme of control
Maintenance and testing records
Action log
Management responsibilities
Site visit/survey
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Review of schematics
Visual inspection
Measurements
Sampling?
BS 8580:2010 Code of Practice
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Risk assessment reporting
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Clear and concise
Formal document
Clear identification of hazard
Clear recommendations
Timescales
Risk review
Key Points from BS 8580:2010
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A clearly defined process for risk assessment
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Competency of the assessor
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Independence
- Impartiality
- Integrity
BS 8580:2010
 Provides clear levels of expectation for:
- Clients
- Providers
- Enforcement
 Raise quality standards
 Reduce incidences of Legionnaires’ disease
 UKAS accreditation.
Management Scheme
An appropriate management scheme will include:
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Responsibility list
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Parameters of the system to be maintained ie. temperatures, flow
rates, biocide levels etc…
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Testing and inspection schedule
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Testing and inspection procedures
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Testing and inspection results
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Details of actions to take with out of specification results
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Training certification
Management System Auditing
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Don’t assume that the system is being followed
Bulmers Cider outbreak 2003 (26 cases and 2 deaths)
Responsible person
Independent third party
Areas of focus
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Completion of monitoring/inspection tasks
Out of specification results
Supporting certification eg. Legionella tests
Verification of results by inspection
Summary
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Safe working environment
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Ensure water is fit for purpose
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Minimise downtime
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Avoid prosecution
Thank You