Decontamination effects, protective clothing

Fortunately, relatively non-toxic derivatives are usually obtained when most nerve gases are broken down by seawater, and this would obviously help with decontamination problems. Decontaminants based on chemical mixtures have been developed. These usually have some drawbacks or are applicable to only one nerve agent, however. Effective protective clothing has been thoroughly developed, particularly by Great Britain and the United States. 

Decontamination This term refers to the removal of hazardous materials from personnel and equipment to the extent necessary to prevent potential adverse health effects. Contaminated clothing and equipment should be removed after use and stored in a controlled area (referred to as the hot zone) until cleanup procedures can be initiated. In some cases, protective clothing and equipment cannot be decontaminated and must be disposed of in a proper manner. 

The responder must have knowledge of the agent, its effects, and countermeasures and knowledge of how to protect self and others, which includes decontamination of self and others. Equipment includes material for countermeasures, such as antidotes if known, and material for protection, such as protective clothing and masks. 

C. Decontamination (see p 46). Properly trained personnel should use self-contained breathing apparatus and chemical-protective clothing before entering contaminated areas. The absence of irritant effects from chloropicrin does not guarantee that It Is safe to enter without protection. 

Commerciai iaundries or cieaning estab-iishments. Commercial laundries or cleaning establishments that decontaminate protective clothing or equipment shall be informed of the potentially harmful effects of exposures to hazardous substances. 

A greater problem arises if the spill occurs in the open laboratory. All laboratory protocols should be designed to prevent such occurrences. In the event of an overt laboratory spill, the first action is evacuation of personnel fi om the affected area to minimize the exposure of personnel and experimental materials beyond those involved in the immediate area of the spill. The decontamination procedures adopted must be effective rapidly and must not create additional aerosol or allow mechanical transfer of materials to unaffected areas. Personnel carrying out the cleanup procedures must wear protective clothing and equipment, including respiratory protection (see Chapter 2). Consideration must be given to the safe disposal of all materials and liquids resulting from cleanup procedures. Reentry of personnel into the area should be avoided until it can be reasonably established that the area has been effectively decontaminated. Further specific details are provided in Appendix 1. 

Unlike conventional explosives, which have instantaneous effects, chemical clouds take time to reach their target. This allows additional time to move out of the way or into a protective enclosure. In the case of civilians, anyone inside a soundly constructed house or car would almost certainly have full protection, even at distances as short as 50 meters, provided the doors and windows are closed. Putting duct tape and plastic over windows (or, as reported recently in one case, over the entire house) makes no sense. The blast effect of a warhead exploding closer than 50 meters would probably be more lethal than its contents of nerve gas. Furthermore, quick decontamination can prevent effects through the skin. Even ordinary clothing provides considerable protection. 

Atmospheric conditions and particle size determine the persistence of aerosolized toxin in the environment. Temperature and humidity extremes facilitate toxin degradation, and smaller particles dissipate more quickly into the atmosphere. Studies estimate that aerosolized toxin would decay between less than 1 and 4% per minute. At a 1% decay rate, insubstantial amounts of toxin would remain after 2 days (36). Although botulinum toxin can penetrate mucosal surfaces, it cannot penetrate intact skin. If a release were recognized or announced, and authorities anticipated potential airborne exposure, people could protect themselves by covering their mouths and noses with clothing, such as underwear, shirts, scarfs, or handkerchiefs. In addition, after exposure, washing with soap and water would decontaminate clothing, and a 0.1% hypochlorite bleach solution would be effective on contaminated objects and surfaces (36). 

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