Information on how the University manages the risks associated from Legionella pneumophila or other related bacteria in water systems
Legionnaires’ Disease or Legionellosis is the term used for infections caused by Legionella pneumophila and other related bacteria. Legionella bacteria are only dangerous in respirable form and generally only to susceptible individuals where inhalation of the bacteria in aerosols or water droplets (typically <5mm) may cause severe pneumonia and, in extreme cases, death.
Legionella bacteria are widespread and found naturally in many aquatic environments, where they feed on algae and organic matter in sludge, sediment and silt. They tolerate a range of temperatures, although below 20°C and above 50°C they are dormant and above 60°C they will not survive.
When Legionella bacteria enter man-made water systems they may proliferate under favourable conditions. If water droplets are then created and dispersed into the atmosphere then people in the vicinity may be at risk of inhaling the bacteria. To eliminate or reduce the risk, control measures must be in place to prevent the proliferation of the organism in water systems, and to minimise the generation of water droplets and aerosols. The following details how the University manages these risks, including information on:
approved code of practice
duty holders and responsibilities
control of Legionella
hot and cold water services
humidifiers and spray type air washers
other equipment which create risk
other activities which create risk
cooling towers and evaporate condensers (including adiabatic systems)