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Technical Decontamination

Technical decon is most commonly performed using a sequential nine-step process originally developed by Noll and Hildebrand (1994). The steps are listed below.

In the Exclusion Zone (Hot Zone—dangerous concentrations of the agent are likely)


Contaminated tools and equipment drop onto a plastic sheet


Contaminated trash drop

In the Contamination Reduction Zone (Warm Zone)


Primary garment wash/rinse (boots, outer gloves, suit, SCBA, and mask)


Primary garment removal


Secondary garment wash/rinse (decontaminate inner protective garment and inner gloves)


Face piece removal/drop (can be combined with stations 7 and 8)


Boot drop


Inner glove removal

In the Support Zone (Clean Zone)


Shower and clothing change

This process is well known and extensively utilized by the public safety community. Cleaning is done using water in conjunction with one of four cleaning solutions, (solutions known as A, B, C, D), depending on the type of contaminant. Solution "A" contains 5 percent sodium bicarbonate and 5 percent trisodium phosphate and is used for inorganic acids, acidic caustic wastes, solvents and organic compounds, plastic wastes, polychlorinated biphenyls (PCBs), and biologic contamination. Solution "B" is a concentrated solution of sodium hypochlorite. A 10 percent solution is used for radioactive materials, pesticides, chlorinated phenols, dioxin, PCB, cyanide, ammonia, inorganic wastes, organic wastes, and biologic contamination. Solution "C'' is a rinse solution of 5 percent trisodium phosphate. It is used for solvents and organic compounds, PCB and polybrominated biphenyls (PBB), and oily wastes not suspected to be contaminated with pesticides. Solution "D" is dilute hydrochloric acid. It is used for inorganic bases, alkalis, and alkali caustic wastes.

Once the decon process is completed, the equipment is most often returned to service, unless the item(s) cannot be completely decontaminated (as determined by using available detection devices). However, current research does not provide an answer to the question, "how clean

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