Legionella
A bacterium found naturally in water that can multiply in artificial water systems such as cooling towers, hot water systems and showerheads, causing Legionnaires disease if inhaled as fine water droplets. Employers must manage legionella risk through a written scheme of control.
Also known as
By jurisdiction
UK HSE
“legionella”Exact equivalentThe Health and Safety at Work etc. Act 1974 and the Control of Substances Hazardous to Health Regulations 2002 (regulation 9) require employers to prevent or control exposure to legionella bacteria. ACOP L8 (4th edition, 2013) — Legionnaires Disease: The Control of Legionella Bacteria in Water Systems — is the main approved code of practice. Employers must appoint a responsible person, carry out a legionella risk assessment, implement a written scheme of control, and maintain records.
Irish HSA
“legionella”Close equivalentThe Safety, Health and Welfare at Work Act 2005 and the Chemical Agents Regulations 2001 apply to legionella as a biological agent. The HSA and the Environmental Protection Agency publish guidance on legionella risk assessment and control. A written risk assessment and control scheme are required for susceptible water systems.
US OSHA
“legionella”Partial equivalentOSHA has no specific regulatory standard for legionella but addresses it through the General Duty Clause (section 5(a)(1)) and enforcement of existing standards. OSHA published a Safety and Health Information Bulletin on legionella prevention. ASHRAE Standard 188 (Prevention of Legionellosis Associated with Building Water Systems) is widely referenced in OSHA enforcement actions.
Practitioner note: Controlled under COSHH 2002 via ACOP L8. A written legionella risk assessment and scheme of control are required for susceptible water systems. OSHA enforces via General Duty Clause.