The PRISM incident response protocols are fit for purpose for ambulatory casualties. However, a more effective communication strategy is required for first responders (particularly when guiding dry decontamination). There is a clear need to develop more appropriate decontamination procedures for at-risk casualties.

A well-established provision for mass-casualty decontamination that incorporates the use of mobile showering units has been developed in the UK. The effectiveness of such decontamination procedures will be critical in minimizing or preventing the contamination of emergency responders and hospital infrastructure. The purpose of this study was to evaluate three empirical strategies designed to optimize existing decontamination procedures: (1) instructions in the form of a pictorial aid prior to decontamination; (2) provision of a washcloth within the showering facility; and (3) an extended showering period. The study was a three-factor, between-participants (or “independent”) design with 90 volunteers. The three factors each had two levels: use of washcloths (washcloth/no washcloth), washing instructions (instructions/no instructions), and shower cycle duration (three minutes/six minutes). The effectiveness of these strategies was quantified by whole-body fluorescence imaging following application of a red fluorophore to multiple, discrete areas of the skin. All five showering procedures were relatively effective in removing the fluorophore “contaminant”, but the use of a cloth (in the absence of instructions) led to a significant (∼20%) improvement in the effectiveness of decontamination over the standard protocol (p <0.05). Current mass-casualty decontamination effectiveness, especially in children, can be optimized by the provision of a washcloth. This simple but effective approach indicates the value of performing controlled volunteer trials for optimizing existing decontamination procedures.

Prompt disrobing and minimization of time to casualty decontamination are key to the effective treatment of individuals exposed to toxic chemicals. Established procedures for mass casualty decontamination that involve the deployment of equipment for showering with water (such as the ladder pipe system [LPS] and technical decontamination) necessarily introduce a short, but critical delay. The purpose of this study was to investigate the effectiveness of dry and wet decontamination approaches (individually and in combination) for removing a chemical warfare agent simulant from the hair and skin of human volunteers. A secondary aim was to quantify potential hazards arising from the decontamination processes. Volunteers were exposed to the simulant (mixture of methyl salicylate, fluorophore [curcumin] and mineral oil) as an aerosol within a custom-built dosing chamber. Three decontamination protocols (dry, LPS and technical decontamination) were applied in various sequences. The efficacy of the protocols was evaluated by whole-body fluorescent imaging and measurement of residual simulant recovered from the hair, skin, decontamination materials and air samples using liquid chromatography and thermal desorption gas chromatography. Dry decontamination before LPS or technical decontamination produced significant reductions in methyl salicylate skin contamination. The greatest reductions were seen with the Triple Protocol (dry, then LPS, then technical decontamination). Secondary sources of contamination (e.g. off-gassing of vapor and residue on wash cloths/towels) decreased following dry decontamination. The introduction of dry decontamination prior to wet forms of decontamination offers a simple strategy to initiate treatment at a much earlier opportunity, with a corresponding improvement in clinical outcomes. Our results confirm the value of a "Triple Protocol" response strategy based on the integration of dry and wet decontamination procedures. 3 Importantly, we highlight how these combined protocols may reduce toxicological risks downstream in the operational process.

The UK is currently in the process of implementing a modified response to chemical, biological, radiological and nuclear and hazardous material incidents that combines an initial operational response with a revision of the existing specialist operational response for ambulant casualties. The process is based on scientific evidence and focuses on the needs of casualties rather than the availability of specialist resources such as personal protective equipment, detection and monitoring instruments and bespoke showering (mass casualty decontamination) facilities. Two main features of the revised process are: (1) the introduction of an emergency disrobe and dry decontamination step prior to the arrival of specialist resources and (2) a revised protocol for mass casualty (wet) decontamination that has the potential to double the throughput of casualties and improve the removal of contaminants from the skin surface. Optimised methods for performing dry and wet decontamination are presented that may be of relevance to hospitals, as well as first responders at the scene of a chemical incident.

Objective: The UK's Initial Operational Response (IOR) is a new process for improving the survival of multiple casualties following a chemical, biological, radiological or nuclear incident. Whilst the introduction of IOR represents a patient-focused response for ambulant casualties, there is currently no provision for disrobe and dry decontamination of nonambulant casualties. Moreover, the current specialist operational response (SOR) protocol for nonambulant casualty decontamination (also referred to as "clinical decontamination") has not been subject to rigorous evaluation or development. Therefore, the aim of this study was to confirm the effectiveness of putatively optimized dry (IOR) and wet (SOR) protocols for nonambulant decontamination in human volunteers. Methods: Dry and wet decontamination protocols were objectively evaluated using human volunteers. Decontamination effectiveness was quantified by liquid chromatography--mass spectrometry analysis of the recovery of a chemical warfare agent simulant (methylsalicylate) from skin and hair of volunteers, with whole-body fluorescence imaging to quantify the skin distribution of residual simulant. Results: Both the dry and wet decontamination processes were rapid (3 and 4 min, respectively) and were effective in removing simulant from the hair and skin of volunteers, with no observable adverse effects related to skin surface spreading of contaminant. Conclusions: Further studies are required to assess the combined effectiveness of dry and wet decontamination under more realistic conditions and to develop appropriate operational procedures that ensure the safety of first responders.

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Mass casualty decontamination is a public health intervention that would be employed by emergency responders following a chemical, biological, or radiological incident. The decontamination of large numbers of casualties is currently most often performed with water to remove contaminants from the skin surface. An online survey was conducted to explore US fire departments' decontamination practices and their preparedness for responding to incidents involving mass casualty decontamination. Survey respondents were asked to provide details of various aspects of their decontamination procedures, including expected response times to reach casualties, disrobing procedures, approaches to decontamination, characteristics of the decontamination showering process, provision for special populations, and any actions taken following decontamination. The aim of the survey was to identify any differences in the way in which decontamination guidance is implemented across US states. Results revealed that, in line with current guidance, many US fire departments routinely use the ''ladder-pipe system'' for conducting rapid, gross decontamination of casualties.The survey revealed significant variability in ladder-pipe construction, such as the position and number of fire hoses used.There was also variability in decontamination characteristics, such as water temperature and water pressure, detergent use, and shower duration. The results presented here provide important insights into the ways in which implementation of decontamination guidance can vary between US states. These inconsistencies are thought to reflect established perceived best practices and local adaptation of response plans to address practical and logistical constraints. These outcomes highlight the need for evidence-based national guidelines for conducting mass casualty decontamination.

Most casualty or personnel decontamination studies have focused on removing contaminants from the skin. However, scalp hair and underlying skin are the most likely areas of contamination following airborne exposure to chemicals. The aim of this study was to investigate the interactions of contaminants with scalp hair and underlying skin using a hybrid in vitro diffusion cell model. The in vitro hybrid test system comprised “curtains” of human hair mounted onto sections of excised porcine skin within a modified diffusion cell. The results demonstrated that hair substantially reduced underlying scalp skin contamination and that hair may provide a limited decontamination effect by removing contaminants from the skin surface. This hybrid test system may have application in the development of improved chemical incident response processes through the evaluation of various hair and skin decontamination strategies.