Medical Aspects of Chemical Warfare (2008) - The Black Vault

Decontamination of Chemical Casualtiesworkload among team members. Failure to enforceappropriate work–rest cycles increases the risk ofinjury and ultimately depletes personnel pools onsubsequent days. Work–rest cycles insure adequatehydration, give the body an opportunity to disperse ex-cessive heat, and slow down the production of internalbody heat created during physical work. Chapter 14,Field Management of Chemical Casualties, providesfurther discussion on work–rest cycles and a table forcalculating them.EQUIPMENT FOR PATIENT THOROUGH DECONTAMINATIONIndividual Protective EquipmentAll decontamination team members must wear IPEfor their protection. 3,44 OSHA and the Federal ChemicalStockpile Emergency Preparedness Program recommendOSHA level C as the most appropriate wearfor first receivers, which include decontaminationteam members. 44,70,71 In the military, MOPP level 4 isroughly equivalent to OSHA level C. OSHA levels Aand B (Exhibit 16-3) are normally worn at an incidentsite (hot zone; Exhibit 16-4) when the contamination isunknown. This high level of protection, which createsan additional heat burden on the worker and restrictsmobility, is not necessary for decontamination operationsin the warm zone, where the chemical risk isgreatly reduced. For more information on OSHA levelssee Chapter 17, Chemical Defense Equipment.Decontamination team members using dry decontaminants,water, soap and water, or other liquiddecontaminants must wear IPE that allows for easyoperator wipe down. The IPE must also preventundergarments from being saturated with water ifwater is used during decontamination. Torngren etal 72 showed that aerosolized agent simulants and theirvapors penetrate protective equipment that becomessaturated with water during patient decontaminationoperations. 72 In this study, the wet underwear of thedecontamination operators became contaminated.Preventing this saturation is best accomplished byEXHIBIT 16-4ZONES OF CONTAMINATIONHot zone: Area of agent release that is directly contaminated.Warm zone (or decontamination zone): Area outsidethe hot zone where contamination consists only of thatbrought into the area by contaminated patients andworkers from the hot zone.Cold zone (postdecontamination zone): Area beyondthe warm zone that is free of solid, liquid, and vaporcontamination. Patients are decontaminated beforeentering this area.Fig. 16-4. An example of a hooded, powered air pressurerespirator with a Tyvek F [(DuPont, Wilmington, Del) overgarment.Note the filter power unit worn at the waist.Photograph by Peter Hurst, US Army Medical ResearchInstitute for Chemical Defense.543