Scalewatcher equipment for the prevention of legionellosis



    A Legionella bacterium, the fundamental agent of Legionnaire’s Disease, is a water based organism, which causes infection when inhaled in an aerosol form. Although normally associated with cooling towers and evaporative condensers it also be found in showers, and has been known to effect workers engaged in the manufacture of plastic parts using injection molding equipment. In the plastics industry the organisms have been found in the water used to cool the metal moulds as well as the process equipment employed during the manufacture of plastic parts.

    Increasing heating charges mean that maintaining hot water systems to the recommended temperature has now become a major cost burden to most organizations. Not only is this not energy efficient, it is not a cost effective way of controlling bacteria.

    Bacteria may be able to colonize certain types of water fitting, pipe work and materials used in the construction of water systems. The presence of such materials and of large quantities of sediment may provide nutrients for Legionella and can make eradication difficult. In practice, LP is found in many recirculation hot and cold water systems particularly in larger, complex systems such as those found in hospitals, hotels, office block and factories. Legionella is transmitted exclusively by inhalation of contaminated water droplets. The organisms must be present in sufficiently high concentration and must be suspended in aerosol between 3 and 5 microns in diameter. There is no evidence of obtaining the disease from ingestion or contaminated water or absorption through the skin. High-risk areas are therefore primarily associated with showers, sprays, spray taps, taps with high water pressure and refrigeration and air conditioning cooling towers.

    Limescale is a major problem in both hot and cold water systems. Dripping faucets can leave sediment in and around the faucet, and at high room temperatures, this is an ideal breeding ground for bacteria. In hot systems, scale can trap Legionella and biofilms. This provides an excellent growing medium that cannot be penetrated by disinfectants. Plaque colonized by Legionella can continuously re-contaminate the system even after disinfection. Entrapped biofilms are a nutrient source for bacteria and can cause taste and odor problems due to the products of their metabolism.

           Limescale is the main cause of inefficiency in hot water systems. Scales on the heat exchange surface significantly reduce heat transfer efficiency and promote corrosion in radiators and pipelines. Descaling a hot water system is time-consuming and expensive. Water softeners can reduce lime scale, but there is growing concern about sodium levels in water increasing to sometimes high levels.

    All systems, cold, hot and process systems, require a continuous scale control method and a water treatment regime that prevents the growth of biofilms, bacteria and especially Legionella. This method is now also available as an electronic water treatment method to prevent lime scale formation along with chlorination of all hot and cold water supplied to a building or plant.

    Water treated with Scalewatcher electronic systems will prevent lime deposits from forming in pipes and on heat transfer surfaces, and will also remove existing scale over time. This engineering solution has many advantages. One of them is removing the source of colonization of biofilms and bacteria (including legionella). 

    Using Scalewatcher will eliminate the conditions for legionella to develop!

    For information and orders, write: or call +370 62168746.