Over the past few years, the numbers of detected cases of Legionnaires’ disease as well as resulting deaths have increased. Although the trend may seem alarming at first glance, it is worthwhile to note that this increase can be attributed largely in part to improved Legionella water testing practices and the heightened awareness of responsible officials rather than an actual increase in cases of Legionnaires’ disease.
Through regular water quality testing, establishments are able to experience multiple advantages, including enhancing the effectiveness of safety measures in place and ensuring worker safety. These advantages lead to more benefits, such as a boost in business reputation and the prevention of costly occupational health and safety risks.
For the most part, efforts to prevent the dreaded disease have been concentrated around hospitals, long-term care facilities for the elderly and other institutions housing at-risk individuals.
However, it is also worthwhile to focus some attention toward commercial establishments, hotels and industrial facilities.
Specifically, in the industrial sector, responsible persons should take the necessary steps to limit, if not totally prevent, the exposure of employees and other stakeholders to aerosols coming from their water systems.
Although the domestic water system is usually associated with bacterial growth, property and business managers should not ignore aerosol exposure from other sources. These include cooling towers, evaporative condensers, fluid coolers, spas and whirlpools, dental water lines, safety showers, stagnant water in fire sprinklers, eye wash systems, humidifiers, and decorative water systems.
Responsible persons should be aware of the conditions that facilitate the growth of Legionella bacteria, including the ideal temperature range, supporting microorganisms, optimal pH levels, and the presence of sediment and scale.
Apart from regular water testing, the appropriate preventive measures should also be enforced in industrial facilities in order to manage facilities that produce water aerosols.
Facilities like heat exchangers and cooling towers, for example, should be cleaned and disinfected on a regular basis. These include using chlorine and other halogen disinfectants, drainage of unused water sumps, minimising the use of water reservoirs, and monitoring the drift from cooling towers, fluid coolers and evaporative condensers. Regular draining and elimination of stagnant water sources along with cleaning and disinfection can also aid in the preventive efforts.
Should the bacteria be detected within the premises of an industrial facility, the recommended remediation focuses on the plumbing system with the end goal of eliminating the biofilms. This can be done using several methods such raising the water temperature to 70°C or using disinfectants such as chlorine, chlorine dioxide or hydrogen peroxide.