Method development for the evaluation of emergency decontamination protocol effectiveness using an ultraviolet fluorescent aerosol

Abstract

After hazardous material incidents, it is important to perform emergency decontamination procedures to remove contamination from the body. As these emergency decontamination procedures are developed, it is important to understand the efficacy of a given protocol. This study discusses a method that was developed to evaluate the efficacy of decontamination procedures by using an ultraviolet fluorescent aerosol and an image analysis protocol. This method involves imaging a mannequin while both unclothed and clothed prior to exposure to the fluorescent aerosol. After exposure, it was imaged again, disrobed, and decontaminated following an unconscious patient wet decontamination method. This work describes in detail the materials and methods used to develop the final methodology. Two clothing types (black cotton and Tyvek) were used to simulate civilian and first responder casualties. Image analysis was used to measure the extent of contamination on the mannequin at each stage of the procedure. These measurements were then compared to determine decontamination efficacy for each step (disrobing, wet decontamination, and total removal). The exposure protocol was shown to provide repeatable deposition of aerosol onto the mannequin. Decontamination was also shown to be repeatable, with no trends toward efficacy changing over time.