Legionella – What is it & what are your duties?
Legionella was discovered after an outbreak in 1976 among people who went to a Philadelphia convention of the American Legion. Those who were affected suffered from a type of pneumonia that eventually became known as Legionnaires' disease.
The first major outbreak in the UK was at Staffordshire Hospital in 1985, where over 100 patients fell ill with pneumonia-like symptoms, 28 of which died. An investigation traced the source of the outbreak to Legionella bacteria in an air-conditioning cooling tower.
Legionnaires’ disease is a potentially fatal form of pneumonia and everyone is susceptible to infection. However, some people are at higher risk, including:
- People over 45 years of age
- Smokers and heavy drinkers
- People suffering from chronic respiratory or kidney disease
- Anyone with an impaired immune system
Where are legionella bacteria found?
The bacterium Legionella pneumophila and related bacteria are common in natural water sources such as rivers, lakes and reservoirs, but usually in low numbers.
Since Legionella bacteria are widespread in the environment, they may also contaminate and grow in purpose built water systems such are cooling towers, evaporative condensers, hot and cold water systems and whirlpools and hot tubs.
Any water system that has the right environmental conditions could potentially be a source or legionella bacteria growth, so is there a reasonably foreseeable legionella risk in your water system:
- Water is stored or re-circulated as part of your system
- The water temperature is all, or some part of the system is between 20 – 45 ◦ C
- There are some sources of nutrients such as rust, sludge, scale and organic matters
- The conditions are likely to encourage bacteria to multiply
If it is possible for water droplets to be produced, they be dispersed over a wide are e.g. showers and aerosols from cooling towers, people are susceptible to infection.
What are your duties?
Under general health and safety law as an employer, or a person in control of a premises e.g. a landlord, you have health and safety duties and need to take suitable precautions to prevent or control the risk of exposure to legionella.
You must appoint a “Duty Holder” to be responsible for managing the risk of Legionella in your premises.
Have you appointed a ‘Duty Holder’ and do they know what to do?
To find out more about how to identify and assess sources of risk why not call us on 01722 326 390 or email firstname.lastname@example.org