Lewisite

CAS RN: 541-25-3

Cleanup Methods

Cover with vermiculite, diatomaceous earth, clay, or fine sand and neutralize as soon as possible using large amounts of alcoholic caustic, carbonate, or Decontaminating Agent (DS2). Caution: acetylene given off. Household bleach can also be used if accompanied by stirring to allow contact. Scoop up all material and place in an approved container. After sealing, decontaminate the exterior and label. All leaking containers will be packed with sorbent (e.g. vermiculite) placed between the interior and exterior containers. Label and dispose according to regulations. Conduct general area monitoring.
Protection: Evacuation: Immediately isolate an area around any liquid or solid contamination for at least 400 feet in all directions. If possible, identify the agent and develop a downwind hazard diagram ... Adjust the initial isolation distance as appropriate. Based on the type of release, amount of material aerosolized, persistence of the agent and local conditions (e.g., weather, population density, time of day), shelter in place until the initial cloud passes may be the most appropriate course of action since timely evacuation of the threatened downwind population may not be possible. Depending on the persistence of the agent and the potential for condensation of agent from the cloud, evacuation of the threatened population after passage of the initial cloud may be appropriate.
Hydrolyzed by alkalies; neutralized and inactivated by bleaching powder, sodium hypochlorite.
Small Areas: Decontaminate with copious amounts of full strength household bleach. Removal of porous material, including painted surfaces, that may have absorbed arsenical vesicant vapor may be required as these materials could continue to re release vapor after exposure has ceased. /Vesicants - Arsenic Based/
Small Areas: Puddles of liquid must be contained by covering with vermiculite, diatomaceous earth, clay, fine sand, sponges, paper towels, or cloth towels. Remove all material & place in a container. Decontaminate the area with copious amounts of household bleach. Removal of porous material, including painted surfaces, that may have absorbed Vesicant liquid may be required as these materials could continue to re release vapor after exposure has ceased. Surfaces contaminated with vesicants, then only rinsed may still evolve sufficient agent vapor to produce a physiological response. /Vesicants- Arsenic Based/
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