March of the Cooling Towers (2000)
how's our back-up system Wikipedia:
Another very important reason for using biocides in cooling towers is to prevent the growth of Legionella which is a Gram negative bacterium, including species that cause legionellosis or Legionnaires' Disease, most notably L. pneumophilia. The various Legionella species are the cause of Legionnaires' Disease in humans and transmission is via exposure to aerosols -- the inhalation of mist droplets containing the bacteria. Common sources of Legionella include cooling towers used in open recirculating evaporative cooling water systems, domestic hot water systems, fountains, and similar disseminators that tap into a public water supply.
Do not operate the tower unattended.
Hey. Homer. Where ya going? Get your mind back on your work...
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