- Smoke hood
A smoke hood is a protective device similar in concept to a
gas mask . Atranslucent airtight bag seals around the head of the wearer while anair filter held in the mouth connects to the outside atmosphere and is used to breathe. Smoke hoods are intended to protect victims of fire from the effects ofsmoke inhalation .High quality smoke hoods are generally constructed of heat resistant material like
Kapton , and can withstand relatively high temperatures. The most important part of a smoke hood is the filter that provides protection from the toxic byproducts ofcombustion . Virtually all smoke hood designs utilize some form ofactivated charcoal filter andparticulate filter to screen out corrosive fumes likeammonia andchlorine , as well as acid gases likehydrogen chloride andhydrogen sulfide . The defining characteristic of an effective smoke hood is the ability to convert deadlycarbon monoxide to relatively harmlesscarbon dioxide through acatalytic process.Smoke hoods present on aircraft, also called Protective Breathing Equipment (or PBEs), typically generate oxygen for approximately 30 seconds. The oxygen is kept in a closed circuit, usually thanks to a tight neck seal. A
scrubber system may be present to reduce the levels ofcarbon dioxide , and is breathable for around 20 minutes. When the oxygen supply ends, the hood must be removed to avoid suffocation.
Wikimedia Foundation. 2010.