Legionella Control and Prevention
Feedwater provide a comprehensive range of products and services for legionella control in water systems and are specialists in Legionnaires Disease prevention.
Because of the significant risk to public health associated with Legionnaires’ Disease and Legionellosis, the control of the bacteria or legionella treatment is regulated by health and safety law in the UK and many other countries. In the UK it is covered by the COSHH regulations and ACoP L8 published by the HSE – “Legionnaires’ Disease: The Control of Legionella Bacteria in Water Systems – Approved Code of Practice and Guidance (L8)” (see link below to download).
Feedwater has vast experience in legionella treatment and we were helping in the prevention of Legionnaires’ Disease before most people had even heard of it. We remain the only UK water treatment company with our own in-house UKAS-accredited laboratory for legionella testing and analysis. Because of our experience and our commitment to protecting public health we were founder members of the Legionella Control Association (LCA) when it was established as the Code of Conduct Association in 1999.
What is Legionellosis and Legionnaires’ Disease?
Legionnaires’ Disease is a form of pneumonia caused by inhaling tiny water droplets (aerosols) which are contaminated with legionella bacteria. It is often fatal, but is wholly preventable. Legionellosis is the name given to a range of illnesses caused by legionella bacteria; as well as Legionaires Disease they includePontiac fever and Lochgoilhead fever which are milder flu-like illnesses.
How do you get legionella in water systems?
Legionella bacteria are commonly found in natural water systems such as rivers and lakes where their numbers are usually low and they pose little risk. They grow over a temperature range of 20°C to 45°C. Below this temperature they survive dormant and as the temperature rises above 50°C they are progressively killed off and will not survive long at temperatures above 60°C. Their ideal growth temperature is around human body temperature, 37°C! Whilst legionella are widely found in the natural environment the risk comes when they contaminate man-made water systems, entering at low levels in the incoming water supply or in air-borne aerosols. Many man-made water systems not only provide the ideal environment for legionella to multiply but also involve water sprays which can release dangerous aerosols into the atmosphere.
What does legionella need to thrive?
As well as a water temperature of 20°C to 45°C legionella bacteria need a supply of nutrients which are usually provided by other microbes which are commonly found in the water. In particular there is a strong relationship between biofilms (microbial slimes), amoebae and the growth of legionella. Biofilms flourish in warm, stagnant water. As a general rule legionella likes dirty systems which are fouled with corrosion products and scale and dislikes clean water systems.