Legionnaires Disease

A potentially fatal form of pneumonia which can affect anybody, but which principally affects those who are susceptible because of age, illness, immuno-suppression, smoking etc.                                             - HSE

Temperature vs Legionella:

  • At 60 °C (140 °F) - Legionella dies instantly - pasteurisation occurs.
  • At 55 °C (131 °F) - 95% die
  • 50 to 55 °C (122 to 131 °F) - Can survive but do not multiply
  • 35 to 46 °C (95 to 115 °F) - Ideal growth range
  • 20 to 50 °C (68 to 122 °F) - Growth range
  • Below 20 °C (68 °F) - Can survive but are dormant, even below freezing

From published Health and Safety Executive guidance for employers