A Guide to Legionella Risk Assessments

The Health and Safety Executive has stated that there is no reason why a landlord cannot carry out this risk assessment themselves, so long as they are competent. We have produced this Legionella Risk Assessment form to act as a framework to assist in making such an assessment.

Inspecting an insulated cold water tank as part of a Legionella risk assessment

Since 2015 it has been a legal requirement that all landlords of residential rental properties have a Legionella Risk Assessment completed and act upon its recommendations.

This assessment must then be reviewed periodically depending on the level of risk. The law does not require landlords to hold a ‘Legionnaires testing certificate', nor is Legionella (laboratory) testing usually required. The Health and Safety Executive has stated that there is no reason why a landlord cannot carry out this risk assessment themselves, so long as they are competent. They should retain reasonable proof that the risk assessment was conducted and that they acted upon its recommendations. The person conducting the assessment should understand the water system and any associated equipment in order to conclude whether the system is likely to create a risk from exposure to legionella. They should also be able to identify whether:

  • water is stored or re-circulated as part of the system;
  • the water temperature in any part of the system is between 20–45 °C;
  • there are sources of nutrients such as rust, sludge, scale or organic matter;
  • conditions are present to encourage bacteria to multiply;
  • is it possible for water droplets to be produced and, if so, whether they could be dispersed over a wide area. e.g. showers and other aerosols;
  • it is likely that any of the tenants or their visitors are more susceptible to infection due to age, illness, a weakened immune system etc. and whether they could be exposed to any contaminated water droplets.

The risk assessment should include:

  • management responsibilities, including the name of the competent person and a description of the system;
  • potential sources of risk;
  • any controls in place to control risks;
  • monitoring, inspection and maintenance procedures;
  • records of the monitoring results, inspections and checks carried out;
  • arrangements to review the risk assessment regularly.

We have produced this Legionella Risk Assessment form to act as a framework to assist in making such an assessment, but it should not be considered exhaustive. If you are in any doubt, seek professional advice.


Sources & further reading:

Health and Safety Executive, (2015). Legionnaires’ disease. [online] Available at: https://www.hse.gov.uk/pubns/priced/hsg274part2.pdf [Accessed 9 Jul. 2015].

Hse.gov.uk, (2015). Legionnaires' disease - Frequently Asked Questions: HSE. [online] Available at: https://www.hse.gov.uk/legionnaires/faqs.htm [Accessed 9 Jul. 2015].

Hse.gov.uk, (2015). Case 357 - Consultants and Letting Agents misinterpreting the risks of exposure to legionella of their tenants. [online] Available at: https://www.hse.gov.uk/myth/myth-busting/2015/case357-consultants-letting-agents-exposure-to-legionella.htm [Accessed 9 Jul. 2015].