Legionella Risk Assessments
Public water supplies in the UK are usually good. Bacteria do occasionally get into mains water but they are normally quite harmless. However, there are very unpleasant bacteria such as E.Coli and Coliforms which can cause upset stomachs, sickness and diarrhoea etc. Under certain circumstances, Legionella Pneumophila can be found and this can lead to Legionnaires’ disease which can be fatal.
Bacteria multiply by dividing into two every twenty minutes. Legionella multiplies at twice this rate to produce, eventually, pneumonia like symptoms and the human immune system is usually unable to cope with this. At present there is no specific antibiotic for Legionella that’s why it is so important that Legionella risk assessments are carried out regularly.
Legionella can only be caught by inhaling infected water droplets (the “sneeze” principle) such as produced by a shower or spa bath. The bacteria only proliferate between 37ºC and 55ºC so hot water should be stored above 60ºC. Industrial cooling towers and certain types of air conditioning are a potential source of Legionella and should be treated and tested regularly. It is important that showerheads are disinfected/descaled regularly.