Hazmat suit
From Wikipedia, the free encyclopedia
A Hazmat suit is a fully encapsulating garment worn as protection from hazardous materials or substances. It is usually combined with some sort of breathing apparatus or protection. It may be used by firefighters, emergency personnel responding to toxic spills, researchers or military personnel.
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[edit] Capabilities
[edit] Overview
Hazmat suits may provide protection from:
- Chemical agents - through the use of appropriate barrier materials like heavy PVC or rubber and Tyvek, and clean breathing air
- Nuclear agents - by including some radiation shielding in the lining, but more importantly, by preventing direct contact with or inhalation of radioactive particles or gasses
- Biological agents - by providing a fully sealed system (often at overpressure to prevent introduction of biological agents even if the suit is damaged) together with an external air source, usually a tank or via hose connection (in laboratories)
- Fire/high temperatures - usually by a combination of insulating and reflective materials
Hazmat suits generally include breathing air supplies to provide clean, uncontaminated air for the wearer. Working in a Hazmat Suit is very strenuous. The suits tend to be less flexible than conventional work garments, and are hot and poorly ventilated (if at all). Therefore use is usually limited to short durations ranging from 0.5-2 hours, depending on the difficulty of the work. Level A suits for example are limited to around 15-20 minutes of work by their air supply.[1]
[edit] Ratings
In the United States, hazmat suits are included in Level A, B or C protective clothing.[2] Level A suits are vapor-tight, providing total encapsulation and a high level of protection against direct and airborne chemical contact. They are typically worn with a self-contained breathing apparatus (SCBA) enclosed within the suit. Level B suits are not vapor-tight and thus provide a lesser level of protection. Level B suits are worn with an SCBA, which may be inside or outside of the suit, depending on the type of suit (encapsulating or non-encapsulating). Level C includes coveralls or splash suits providing a lesser level of protection than Level B and are typically worn with a respirator or gas mask only. Level D protection also exists, but does not include a 'hazmat suit', as it only requires specific work clothing and eye protection.
Level A suits are constructed of several layers and, being airtight, include a release valve so the suit does not overinflate from exhaled air from the SCBA. Level B suits more closely resemble one-piece Tyvek coveralls used in construction, but may also be fully encapsulating suits which are not airtight. Level C suits may be coveralls of treated material or multi-piece combinations sealed with tape. This kind of protection is still proof against many non-invasive substances, such as Anthrax.[1]
[edit] In fiction
Hazmat suits have long been an important device in fiction, especially science fiction, to accentuate the lethality of environments. Common dramatic situations usually involve a suit failure leading to rapid death in films such as The Andromeda Strain or Outbreak. Plot resolutions usually make the removal of a suit a pivotal moment, signifying the end of the threat.
The anonymity provided by hazmat suits has often been used to accentuate sinister motives, the scientists in E.T. are a good example of this, as are the farcical squad of hazmat encased characters in the animation Monsters Inc.
A contemporary fictional example of the hazmat suit is perhaps best demonstrated by the Hazardous Environment Suit as worn by Gordon Freeman in the Half-Life series of computer games. In this context, Freeman's H.E.V. suit is used as an explanation for his resistance to environmental hazards and physical damage, the suit also having some of the properties of power armour. A Hazmat suit also appears in the game Deus Ex, and can be used temporarily when entering hazardous environments.
This device is also used frequently in the science fiction TV series Stargate in order to avoid alien pathogens.
[edit] References
- ^ a b Hazmat training reveals dangers - The Cincinnati Enquirer, Monday 19 November 2001
- ^ Protective Clothing - Hazmat Gear (from the Santa Clara County Fire Department's website)
