The last decade has seen a fourfold increase in the number of casualties from transportation incidents involving hazardous materials. Responder groups often cannot manage such incidents effectively because they lack knowledge of the chemicals involved, the peak concentrations present in the atmosphere, or the spatial extent of the hazardous zone. A systematic approach to providing responder groups with appropriate instrumentation needs to be developed. An introduction to the categorization of user needs is presented in terms of four types of constraints: time available for response, nature of the spill and the chemicals involved, responder expertise, and spatial extent of the impacted area. An overview is also provided of the general classes of instrumentation that should be considered.

Ovdr the past decade, there~ as been a fourfold increase in the number of casualties from transportation incidents involving hazardous materials. In turn, the number of reported incidents over the same period has increased about eightfold (perhaps partly the result of stricter reporting pressures). Figure