Pre-decontamination triage aims to prioritize the use of decontamination facilities for casualties based on their severity of injuries. Pre-decontamination triage aims to: (1) ensure severe casualties undergo early decontamination, in order for them to receive early definitive medical treatment post-decontamination; (2) provide basic life support measures, e.g., stopping external hemorrhage, use of bag valve mask ventilation, even before decontamination; (3) early administration of antidotes for organophosphate poisoning (if present). Triage during the pre-decontamination takes place in the warm zone. Triage personnel must don personnel protective equipment (PPE) of level C or above. Donning PPE will decrease the visual, aural and tactile senses of triage personnel, adversely affecting their ability to carry out effective triage. With these limitations in mind, a pre-decontamination triage system was devised, modified from the Simple Triage and Rapid Treatment (START) protocol. Assessment will be based on the presence of airway, breathing, or circulatory compromises, or changes in mental status, similar to the START protocol. Recognition of organophosphate poisoning prior to decontamination is emphasized, as the toxidrome is recognizable and specific. Once organophosphate poisoning is diagnosed, the severity of the poisoning is graded and antidote administration is carried out using the Mark I Kits. The need to be certain of the diagnosis of organophosphate poisoning before administration of Mark I Kits is emphasized. The diagnosis may not be apparent initially to the triage personnel till a spectrum of patients with toxidromes suggestive of organophosphate poisoning has been seen.