Legionella

Legionnaires disease

Legionellosis is the term for infections caused by Legionella Pnuemophila with the best known illness being Legionnaires Disease. This is a type of pneumonia that principally affects people that are susceptible due to age, illness, immuno-supression, smoking and can be fatal. The bacteria can also cause less serious illnesses which are not fatal or permanently debilitating, but which can affect all people.

The risk

Legionella can enter water systems and have no affect on people working or living in a building. A number of conditions are required to create the risk of Legionnaires Disease, there are:

  • Conditions suitable for multiplication of the organisms to high numbers, such as temperatures of 20oC to 45oC.
  • A source of nutrients from sludge, scale, rust, algae and other organic matter.
  • A means of creating and spreading breathable droplets, such as the aerosol generated by a cooling tower or shower.
  • Susceptible individuals.

Symptoms

Typical symptoms include fever, headache, muscle pains, difficulty in breathing, cough, diarrhoea, vomiting and mental confusion.

Premises are at risk

 These include premises with water systems incorporating a cooling tower or evaporative condenser, buildings with large and complex hot and cold water systems, any building where the occupants are particularly susceptible (e.g. hospitals, residential care and nursing homes etc.), leisure centres and spa pools etc.

This site provides information on Legionella and how to control risks from exposure to Legionella from manmade water systems.

It will help employers and those with responsibility for the control of premises understand what their duties are and how to comply with health and safety law 

Legal requirements

The Control of Substances Hazardous to Health Regulations 2002 (COSHH) relates to the risks from hazardous micro-organisms, including Legionella and chemicals such as biocides and chlorine. Under these Regulations risk assessments and the adoption of appropriate precautions are required to be made.

The Approved of Code of Practice and Guidance - The control of Legionella Bacteria in Water Systems sets out further statutory requirements for dealing with this risk.

Further Information

The Health and Safety Executive (HSE) website provides detailed information on Legionella and how to control risks from exposure to Legionella from manmade water systems. It will help employers and those with responsibility for the control of premises understand what their duties are and how to comply with health and safety law. 

Further guidance on how to manage and control the risk from legionella in spa pools can be found on the Public Health England website.