Day: May 23, 2022

Legionnaire’s disease is a potentially fatal form of pneumonia which can affect anybody, but which principally affects those who are susceptible because of age, illness, immune suppression, smoking etc. It is caused by legionella bacteria, which can grow in water kept at unsuitable temperatures (between 20ºC and 45ºC) and infect the water in cooling towers, whirlpool spas and purpose built hot and cold water systems, as found in care settings.

Where conditions are suitable for the growth of legionella the risk is increased. There is a risk of disease when droplets of water, infected with the bacteria, are inhaled. Whilst showers may present a particular problem in care homes, water droplets created from taps is also a potential source. Any equipment that can generate water droplets that could be inhaled should be assessed for potential risk.

Under the Health and Safety at Work etc Act 1974 you have a duty to consider the risks from legionella that may affect people in your care, your employees and any visitors. Furthermore, the Control of Substances Hazardous to Heath Regulations 1999 and the Management of Health and Safety at Work Regulations 1999, require you to assess the risks to health posed and then determine what measures can be taken to reduce the risk.

This needs to be completed by a competent person, who understands the risks and can identify suitable controls to be put in place. The Risk Assessment should include legionella preventie identification and evaluation of potential sources of risk, for example:

Whether suitable conditions for bacterial growth exist. i.e. a water temperature range of 20ºC and 45ºC and a supply of nutrients within the system such as sludge, scale, rust, algae and other organic matter.
Whether there are means of creating and disseminating breathable droplets, for example aerosol spray from showers or taps.

The presence of vulnerable people who may be exposed.

Whether conditions allow water to stagnate within the system, for example, if the calorifier or any significant part of a hot water system is put on standby use or are taken out of service for more than one week, if there are any infrequently used or redundant showers and taps, and whether there are any dead legs in the pipework. It would be useful to draw a schematic diagram of the water system to help identify any specific areas that may pose a risk, and to indicate monitoring point (see “monitoring” below) The Risk Assessment must identify control measures to prevent or control exposure to legionella bacteria: