Legionnaire’s Disease is contracted by inhaling droplets of water which contain the Legionella bacteria and those with weaker immune systems are particularly at risk. Although the Legionella bacteria can be found in most water systems, the main areas of risk are where the bacteria can multiply and increase to dangerous levels. This is where water of between 20 and 45 degrees can become stagnant and there is rust, sludge, scale or organic matter for the bacteria to feed upon and multiply. This means that most modern water systems will not require any action further than the carrying out of a risk assessment but old water systems and dirty or poorly maintained air conditioning systems may require further work to be carried out.
The HSE has recently changed its Code of Practice for Legionnaire’s Disease and water systems of a volume of less than 300 litres are now included. This means that landlords now need to carry out appropriate risk assessments otherwise they may risk prosecution. The risk assessment may be carried out by a third party or the landlord if he is competent to do so but the ultimate responsibility is the landlords.
A risk assessment should ask the following questions:
Is the water stored between 20 and 45 degrees?
Is there stagnant water in any areas of the water system, for example redundant pipework?
Is there rust, sludge, scale or organic matter in the system?
Do the thermostatic valves on outlets release water within the above temperature range?
Are there any outlets which are not frequently used, for example showers or taps in second bathrooms?
You should also consider whether your tenants are particularly at risk due to age, illness or weakened immunity.
Where a risk is identified then steps should be taken to deal with it, such as flushing out the system, avoiding debris getting into the system, maintaining the correct temperature and advising tenants of the risks and how to avoid them (for example, flushing out system after periods of lack of use). If any redundant pipework is identified then this could also be removed. The risk assessment should be reviewed regularly and whenever any element of it changes, ie. Vulnerable tenants move in, and written records should be kept of risk assessments and when they are carried out.