Legionella risk assessment and testing: what are a landlord’s responsibilities?

As a landlord, you have certain legal responsibilities when it comes to the health and safety of your tenants, which includes assessing and controlling the risk of legionella exposure in your rental property. Here’s how to go about it.

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Landlords’ legionella responsibilities

Legionella is a type of bacterium found in water, which can cause a pneumonia-type disease called Legionnaire’s disease. Legionella is found naturally in freshwater, but can contaminate water systems (water tanks and hot tubs, for example) and then cause illness if people breathe in contaminated air.

Landlords are responsible for keeping their properties safe and free from health hazards, and when it comes to legionella, this means assessing the risks and taking measures to control them if necessary.

Legionella risk assessment template

In most houses and flats, the risk of legionella contamination is relatively low, but it’s a good idea to do a legionella risk assessment to make sure you’ve identified any areas of concern. Most landlords can assess the risk themselves and can also implement simple measures to keep the risk low.

When you’re doing a legionella risk assessment, consider the following points:

• When was the water system in the property last used? If it hasn’t been used for a while or it isn’t used regularly, this could increase the risk of contamination. The Health and Safety Executive (HSE) advises that hot and cold systems should generally be used at least once a week, and that flushing or draining the system may be necessary during periods when the property is vacant.
• Do you have any water tanks, or is the property’s water entirely supplied by the mains? Water tanks pose more of a legionella risk, as the water has the chance to stagnate.
• How is the water temperature in the property? If the cold water is running cold and the hot water is running hot, this should decrease the risk of contamination, as legionella thrives in warm water. The minimum recommended temperature for hot water stored in tanks is 60 degrees centigrade.
• Do you have instantaneous water heaters (like combi boilers and electric showers) in the property? If so, this should lower the risk, as water is heated as it’s used rather than being stored.
• Are showerheads regularly cleaned and disinfected? This should help control risk.

In summary, you should be thinking about the temperature and movement of the water in your property. You can use a legionella risk assessment template like this free one from the RLA to go through the systems in your property and identify any risks.

It’s worth saying that although completing a risk assessment template is a good idea and could be useful for your own records, you’re not legally required to record the findings of your legionella risk assessment. This is only a legal requirement for businesses with five or more employees.

Controlling the risk of legionella

There are a number of things you can do to help keep your rental property water supply free from legionella. For example:

• Flush the water system before you rent your property, or after it’s been empty for a while.
• Make sure that debris and dirt can’t enter the system, for example by fitting a tight lid over any cold water tanks.
• Make sure that the temperature setting is high enough on your immersion heater or water tank.
• Remove any redundant pieces of pipework.

You can do these tasks yourself if you feel capable, or you can call in a plumber to help.

You should also make sure your tenants are aware of the risks of legionella and that they play their own part in reducing the risk. For example they should:

• Tell you (or the letting agent) if the hot water temperature is too low, or if the hot water isn’t working properly.
• Tell you (or the letting agent) if they notice any debris in the water.
• Turn on water outlets that aren’t used very often (a tap in a guest bedroom, for example) for a couple of minutes each week.
• Clean and disinfect shower heads at least once every six months.
• Leave the water temperature settings at the level you've set them.

It’s a good idea to put this in writing - as part of the rental property manual, for example - for your tenants to refer to.

How to test for legionella

For many landlords, the risk assessment won’t identify any serious legionella risks and so no further action needs to be taken. If this is the case, be sure to keep any existing risk-controlling measures in place, and to assess the risks again if anything changes, and at the start of a new tenancy. Health and safety law does not require landlords to get a legionella test certificate, and the HSE says that legionella testing is only very rarely necessary for domestic water systems.

However, if your risk assessment has identified a reason for concern, you may decide to test the water for legionella. You can do this yourself: there are a number of companies that will post you a kit, which you can send back for lab testing. The cost of the legionella testing kit is usually around £40-£50. Once the legionella test is complete, the lab will send you the results. They will usually send you a test certificate, or provide follow-up advice if legionella has been detected.

What are your top health and safety tips for other landlords? Tell us in the comments.