Legionnaire’s disease is a potentially serious lung infection caused by the Legionella bacteria. It is most commonly caught by inhaling small droplets of contaminated water, for example through air conditioning systems. It has the potential to be fatal, especially to the elderly or the infirm. The disease cannot be passed via human to human contact so any epidemics can usually be traced to a particular building complex. Happily, taking preventative measures is straightforward.

Regulatory requirements

Although relatively rare, it is such a severe illness that residential landlords are required under the Health and Safety at Work etc. Act 1974 (HSWA) to assess and mitigate risks from legionella bacteria. The Management of Health and Safety at Work Regulations (MHSWR) were designed as a fairly broad framework in controlling health and safety at work whilst the Control of Substances Hazardous to Health Regulations 2002 (COSHH) provides landlords and other business owners with a set of actions. These are designed to assess, control and prevent any risk from bacteria such as Legionella. Landlords are required to undertake risk assessments on all of their properties.

Risk assessment

The HSE Approved Code of Practice: Legionnaires’ disease: The control of Legionella bacteria in water systems (L8) provides detailed guidance on managing and controlling risks in water systems. The prescribed risk assessment is designed to check for the presence of risk factors. If the risk of Legionellosis infection is low, no further action is needed for another two years or unless the situation changes. But if one or more risk factors are found, further control measures will be required before the property can be deemed to be safe to let.

To assess whether the water system is likely to constitute a risk, the following questions must be answered:

– Is the water re-circulated or stored within the system?

– Is the water temperature in any part of the system between 20-45 Celsius? The Legionella bacteria cannot multiply in temperatures above or below this range.

– Are there any stagnant water areas, for example in unused pipework or appliances? If the property has been vacant for some time, it is particularly important to flush through the system and to take a control check for bacteria.

– Are there are any deposits of rust, scale or sludge that could potentially support bacterial growth?

– Is it possible for water droplets to occur and, if so, it is likely that any residents, contractors or visitors could be exposed to contaminated water droplets?

Minimising cost

In the vast majority of cases, occupied residential properties with domestic water systems and regular water usage constitute a very low risk. However, as the market leader in letting inventory management, InventoryBase has helpful functionality for risk assessment recording and reporting. The information is simple to record and to access online, minimising administration and ensuring that the information is available on demand.