What is Legionella’s Disease?

Legionella’s disease is a form of pneumonia caused by bacteria in the water supply. It has the potential to be fatal. Legionella bacteria are widespread in water between temperatures of 20 degrees and 45 degrees centigrade. This is the temperature range often characteristic of domestic and commercial property water systems.

Infection is usually due to inhalation of water droplets contaminated with Legionella bacteria.

How is Legionella bacteria controlled?

Legionella bacteria do not proliferate above 60 degrees Centigrade. The initial step is ensuring that water is stored over 60 degrees centigrade. Next is to make sure that hot water reaches the tap quickly, ideally in less than a minute.

How does a Legionella’s survey help?

Amongst other things a Legionella’s surveyor will first make a plan of the water system. They will need to measure the temperature of stored water and measure the time it takes for hot water to get to distribution points. This leads to a substantial report describing the current situation and ways that the hot water system can be made safer.

Whose responsibility is Legionella control?

Initially the landlord but the responsibility can be handed over to a management company.

Read more on the Health and Safety Executive website.

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