Technical options for protecting civilians from toxic vapors and gases

Abstract
Costs and quantitative estimates of effectiveness of general technical options for protecting civilians in place against very toxic vapors are provided and compared with possible hazards. Useful protection can be obtained by taking refuge in enclosed spaces if the leak rate is low, cloud passage is quick and it is possible to tell when the cloud has passed. A variety of charcoal filters and masks are available in the US and abroad which give good protection at reasonable prices if there is some system to warn the people to use the protective equipment. The most cost-effective method of protection found is a mouthpiece respirator which costs less than $14.00 and can be donned in seconds. Protection for a single room in a residence by a charcoal filter and blower can be obtained for under $1000. In cool weather, the population of a mass shelter can be provided with a charcoal-filtered air supply (of 3 cfm per person) for about $10/person. 14 refs., 6 figs., 4 tabs.