Legionella Risk Assessments for Landlords: What You Need to Know

Do Landlords Need a Legionella Risk Assessment?

Yes. Landlords in England have a legal duty to assess and control the risk of tenants being exposed to legionella. According to the Health and Safety Executive (HSE), this doesn't require an in-depth assessment. Most landlords can do it themselves, water testing isn't usually needed, and the law does not require a "legionella test certificate". (HSE: Legionella and landlords' responsibilities)

Legionnaires' disease is a potentially fatal form of pneumonia. People catch it by breathing in small droplets of water containing legionella bacteria. The risk in most rented homes is low, but assessing it is still a duty. Low risk means the assessment is quick; it doesn't mean you can skip it.

Where the Duty Comes From

HSE's position (landlords' responsibilities):

• Who counts as a landlord: anyone who rents out a property they own under a lease or licence shorter than 7 years. This includes renting out a room in your own home.
• The law: section 3(2) of the Health and Safety at Work etc. Act 1974 applies health and safety duties to landlords, who are treated as self-employed for this purpose. The Control of Substances Hazardous to Health Regulations 2002 (COSHH) set out how to identify, assess and control the risk. HSE's Approved Code of Practice L8 gives guidance on these requirements.
• Written record: not a statutory requirement for most landlords. HSE says recording is only a legal duty for employers with five or more employees, but you may find it wise to keep one.
• Review frequency: the law doesn't set an annual or two-yearly review. HSE says to review the assessment periodically in case anything changes.
• Inspection and liability: HSE and councils don't proactively inspect homes for legionella assessments. If a tenant caught Legionnaires' disease from the water system, though, you could be prosecuted and would have to show a court that you had met your duty.

What Makes a Water System Higher or Lower Risk

Legionella multiplies in water between 20°C and 45°C. It is dormant below 20°C and doesn't survive above 60°C (HSE). Risk rises where water is stored or recirculated, where deposits such as rust, scale, sludge or biofilm give bacteria nutrients, and where outlets such as showers create breathable droplets (HSE: what is Legionnaires' disease).

HSE's example of a typical low-risk home has all of these features:

• daily water use enough to turn over the whole system
• cold water direct from the mains, with no storage tanks
• hot water from instantaneous or low-volume heaters, supplying outlets at 50°C
• only toilets and wash hand basins as outlets

HSE adds that instantaneous heaters such as combi boilers and electric showers lower the risk further, because they don't store water. Showers do create droplets, but regular use reduces the risk.

A property with a hot water cylinder, a cold water tank in the loft, long runs of little-used pipework, or long empty periods needs more attention. It doesn't necessarily need a specialist.

Self-Assessment Checklist

Every item below comes from HSE's guidance for landlords, except the temperature checks, which follow HSE's hot and cold water system guidance. Work through it for each property. Note what you found and the date, and keep it with your compliance records.

1. Describe the system. Is hot water from a combi boiler or other instantaneous heater, or from a storage cylinder? Is there a cold water storage tank? List the outlets, including showers and any outside tap.
2. Cold water tank, if there is one. Check it has a tight-fitting lid and no debris can get in.
3. Hot water cylinder, if there is one. Check the thermostat is set so water is stored at 60°C.
4. Temperatures at the taps. Hot water should reach at least 50°C within one minute of running. Cold water should be below 20°C. A cheap thermometer is enough.
5. Redundant pipework. Any "dead legs" (pipes that no longer lead to a used outlet) should be removed.
6. Before each new tenancy. Flush the system through by running the taps and showers.
7. Empty periods. Outlets should be used at least once a week. If the property will be empty for a long time, set up a flushing routine or drain the system.
8. Tell the tenant. Ask them not to change the hot water cylinder's temperature setting, to clean and disinfect showerheads regularly, and to tell you if the hot water isn't heating properly.
9. Plan the review. Reassess when something changes, such as a new boiler, a tank being added or removed, a long empty period, or a tenant reporting a problem. If you can't easily get into an occupied home, HSE suggests checking the water system during visits you already make, such as the annual gas safety check.

If you aren't confident you can judge the system, HSE says you can arrange for someone else to do the assessment on your behalf. This makes most sense for larger HMOs or properties with stored water.

Frequently Asked Questions

For your other recurring safety duties, see our guides to smoke and carbon monoxide alarms and fire safety in rental property. This guide is general information, not legal advice.