To comply with their legal duties, employers and those with responsibilities for the control of premises should; identify and assess the sources of risk (e.g. water temperatures between 20-45ûC, means of creating aerosols and susceptibility of exposed persons), prepare a scheme for preventing or controlling these risks, implement and manage these precautions, keep records of precautions and monitor their effectiveness and appoint a person to be managerial responsible. Legionnaires’ Disease is a potentially fatal form of pneumonia, which can effect anybody but principally effects those persons susceptible because of age, illness, immunosupression, smoking etc. It is caused by the bacterium Legionella pneumophila. On average there are approximately 200-250 reported cases of Legionnaires’ disease each year in the UK.
- Legionella bacteria are common and can be found naturally in environmental water sources such as rivers, lakes and reservoirs and can survive under a wide variety of environmental conditions. Legionella bacteria enter the man-made water system via mains water and if conditions such as water temperature and presence of nutrients allow then the bacterium can proliferate. To reduce the risk of colonisation of the water system the temperature of the stored water should be controlled.
- Legionella isolation including serogrouping of positive isolates is carried out in accordance with the laboratories documented in-house method based on the British Standard. A ten-day test is carried out and clients are notified of positive results and any necessary remedial action. The laboratory operates a minimum detection limit of <100cfu/l as recommended in the Approved Code of Practice L8/2001.