Physical decontamination

F. Chemical inactivation using alkalis is effective, whereas chlorinating is ineffective against phosgene oxide. The eyes should be flushed immediately using water or isotonic sodium bicarbonate solution if available. Physical decontamination of the skin using adsorbent powders, e.g., fullers earth, is advised. 

Physical decontamination of victims is the removal of hazardous substances from victims to prevent or reduce toxicity. Decontamination reduces the amoimt of toxic material to which the victim is exposed and also reduces the risk of secondary contamination (cross-contarnination) of rescuers and others at the scene or the hospital. 

If decontamination caimot be left to natural processes, chemical neutralizers or means of physical removal must be employed. In general, the neutralizers are of two types chlorine-based oxidants or strong bases. Some neutralizers have been especially developed for the decontamination of chemical agents. 

As concentrations of contaminants increase, the potential for permeation of PPE increase. The chemical and physical compatibility of decontamination solutions and methods with selected PPE should be determined before use [2]. 

The plan must include a list of all emergency equipment at tlic facility (such as fire cxtinguisliing systems, spill control equipment, internal and c.xtcrnal communications and alarm systems, and decontamination equipment). In addition, the plan must include for each item on the list a physical description, a brief outline of its capabilities, and its location... 

The chemical and physical compatibility of decontamination solutions or other decontamination materials must be determined before use. Any decontamination method that permeates, degrades, damages, or otherwise impairs the functioning of the personal protective equipment (PPE) is incompatible with such PPE and should not be used. If a decontamination method does pose a direct health hazard, measures must be taken to protect both decontamination personnel and the workers being decontaminated. Figure 16.22 presents a decision aid for the evaluation of health and safety aspects of decontamination methods. 

Stations should be separated physically to prevent cross-contamination and should be arranged in order of decreasing contamination, preferably in a straight line. Separate flow patterns and stations should be provided to isolate workers from different contamination zones containing incompatible wastes. Entry and exit points should be conspicuously marked, and the entry to the CRZ from the exclusion zone should be separate from the entry to the exclusion zone from the CRZ. Dressing stations for entry to the CRZ should be separate from redressing areas for exit from the CRZ. Personnel who wish to enter clean areas of the decontamination facility, such as locker rooms, should be completely decontaminated. 

Countries and groups that lack access to nuclear weapons may still have opportunities to obtain radioactive materials such as spent nuclear fuel. A bomb in which a conventional explosive charge causes dispersal of radioactive material is known as a dirty bomb. Such a device could result in psychological effects exceeding the physical damage it caused. Once again, new techniques are needed for detection (of both the explosive and radioactive material), and decontamination procedures would be essential if such a device were used. 

Metcalfe, D.E., Zukovs, G., Mackay, D., Paterson, S. (1988) Polychlorinated biphenyls (PCBs) physical and chemical property data. In Hazards, Decontamination and Replacement of PCB A Comprehensive Guide. Crine, J.P., Ed., pp. 3-33, Plenum Press, New York. 

Traditionally, passive defence has been the preferred way to counter the BC-threat, however. Passive defence encompasses the whole array of measures that are available to the soldier detection and identification, physical protection, medical countermeasures and decontamination. 

Decontamination The physical and/or chemical process of reducing and preventing the spread of contamination from persons and equipment used at a hazardous materials incident. 

Mustard gas, 5 815, 816-818 decontamination, 5 837 physical properties, 5 817t Mustard seed, 23 168-169 Mutagenesis... 

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