Landlords and employers have a duty to assess the risk from legionella in their water systems. For a typical rented home, office or shop, HSE says a simple assessment is often enough and most landlords can do it themselves.
Under health and safety law, landlords and employers must assess the risk from exposure to legionella and control it. Employers with 5 or more employees must record the significant findings. HSE advises keeping records for as long as they are current and for at least 2 years after, and monitoring records for at least 5 years.
Legionella bacteria grow between 20°C and 45°C. Keeping hot water hot (stored at 60°C), cold water cold and water moving are the main controls in ordinary buildings.
Yes. HSE says most landlords can assess the risk themselves and do not need to be professionally trained or accredited. If you are not confident, get someone competent to do it.
Whenever something changes, such as new pipework, a new boiler or a change of occupants, and regularly in between.
Sources: HSE “Legionella and landlords’ responsibilities” and “Monitoring and keeping records”, checked October 2026. Larger or complex systems (cooling towers, spas, care settings) need the full HSE ACOP L8 approach and a competent assessor.
Related: fire risk assessment · HMO fire safety