DERBY, England, October 22, 2010 /PRNewswire/ -- With no culprit yet announced following the recent fatal outbreak of Legionnaires' disease through the South Wales Valleys, questions are being raised about old machinery putting our health at risk. In August the disease left twenty victims in hospital and claimed two fatalities. Authorities' investigations have centred on water treatment plants in the region, but worryingly no definite source has yet been found.

One possible culprit: unhygienic, outdated mechanical seals from as far back as the 1970s, still in use on public water processing pumps. These machine parts typically feature 'bug traps' which are almost impossible to clean properly, and which can cultivate disease.

According to a spokesperson from the Public Health Agency, The control of Legionnaires' disease in a water system is through good engineering design and maintenance [...] any areas where there can be a build up of dirt and/or scale can be a reservoir for bacteria growth (not just Legionella), particularly where there is stagnant water.

Despite this, the problem remains far more widely spread than we would ever like to believe. According to Alan Roddis, Engineering Director of mechanical seal manufacturer AESSEAL ( ) and ( a worrying fact is despite being published nearly a decade ago, very few seal designs in process equipment in the food and drink industry today conform with the EHEDG (the European Hygienic Engineering and Design Group) basic recommendations.

Unhygienically profiled mechanical seal designs can present a danger to human consumption as the cavities and crevices which contact the processed fluid, are practically impossible to thoroughly clean as explained in the article, The importance of hygienic seal design, November 2010, World Pumps.

The mechanical seal is an important part of any water pumping system. They are designed to stop leaks; keeping water in and contaminants out, but the designs are often complex and unhygienic. Like a chipped cup, some older designs provide hard to clean areas which could become a fortress for the disease.

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Three full quotes from strong sources including PHA available at

Sam Smith AESSEAL plc Tel: +44(0)1709-514-081


CONTACT: Sam Smith, AESSEAL plc, Tel: +44(0)1709-514-081,