Legionella is a bacteria species that can cause a fatal form of pneumonia called Legionnaire’s disease. Man-made water systems provide the perfect conditions for this bacteria to multiply. This is mainly because of the presence of nutrients and instances of stagnation. If you’re an employer, it is your responsibility to ensure water systems in your company’s premises are properly maintained.
To prevent the propagation of the bacteria, Legionella control should be strictly implemented .These involve the following:
It is essential that employers conduct an assessment of potential exposure. This is because the control measures would depend on the result of the Legionella risk assessments. Controls may include water treatment, proper cleaning, and disinfection.
Maintain temperature and sanitation
There are two important factors for preventing the spread of Legionella. These are temperature and sanitation. Water should be cooled to below 20ºC or heated to above 60ºC. It should also be kept free of any contaminants and never be allowed to remain stagnant.
Treat water with chlorine
Chlorine offers an effective chemical treatment. For water systems with low levels of Legionella, chlorine provides results at 0.5 parts per notation. For systems with considerable bacteria levels, temporary shock chlorination may be effective. This involves raising the levels above two ppm for a 24-hour period or more, before lowering it back to 0.5 ppm.
Hyper-chlorination may also be done. This involves taking the water system out of service and raising the chlorine residual to 50-100 ppm or higher for 24 hours or longer. After that, the system is flushed and chlorine residual is lowered back to 0.5 ppm.
Preventing a water system from hosting low levels of Legionella may be impossible. It is, however, possible to keep it from spreading to dangerous levels. The key is to devise proper control measures to hinder bacteria growth.