Published 2nd July 2018

Each year over 300 cases of legionnaires disease are reported in England and Wales, with 10 -12% of those cases proving fatal. For those that recover the disease is often debilitating with recovery taking between 12 – 18 months and survivors often left blind, deaf, or suffering from a loss of limbs due to complications. The disease is contracted through inhaling aerosols of water containing the Legionella bacteria. The bacteria proliferate at temperatures between 20-45°C, within bodies of stagnant or slow moving water. Once within the human lung, the number of bacteria increase significantly and produce toxins. Within transient geotechnical or geoenvironmental sites, respirable water aerosols may be encountered associated with mobile welfare units, drilling mists, emergency showers, temporary water storage drums, dust suppression systems or jet washers. Transient sites have been defined as short duration workplaces where mains water supplied welfare facilities is generally not available.