Dow's chemical exposure index guide

A number of events in the 1970's and 1980's impacted the course of process safety. Incidents such as Flixborough, Seveso, Three‐Mile Island, and Bhopal are well known throughout industry and are recognized as examples of major disasters. Even though events leading up to these disasters were completely different they had one common element between them: a substance was released from a manufacturing unit, became airborne and presented a hazard of such magnitude as to place the safety of both employees and the surrounding public in jeopardy. As a result, industry became increasingly concerned regarding potential loss, in human and economic terms, as plants and equipment grew in size [1]. The Flixborough incident raised the level of concern for process safety, particularly in terms of the hazards presented by fire and explosion. Seveso and Three‐Mile Island emphasized the need to consider far‐field exposure. The Bhopal incident created an urgent need to recognize and understand the expected downwind impact of potential releases of acutely toxic substances to the air. In order to meet this need, the Dow Chemical Company, a recognized leader in the area of safety and loss prevention, presented a Chemical Exposure Index in 1986. AIChE has recently published an updated version entitled Dow's Chemical Exposure Index Guide (first edition). The above publication appears as an AIChE Technical Manual entitled Dow's Chemical Exposure Index Guide [ISBN 0‐8169‐0647‐5] and is available through the AIChE Customer Service Department, 345 East 47th St., New York, N.Y. 10017. Telephone: 1‐800‐242‐4363.