Field trials--measuring progress in pollution prevention using a chemical hazard score

The purpose of this investigation was to demonstrate the feasibility of a method to quantitatively measure achievement (or non-achievement) of reduced pollution generation at the source process in manufacturing, known as pollution prevention. This is societally useful since managers often need quantitative results to justify allocation of resources and United States law has designated pollution prevention as the preferred strategy for managing potential release of hazardous wastes and emissions to the environment. This paper reports the first organized field trials to test the use of the Purdue chemical hazard score to measure progress in pollution prevention. The tests were conducted of 16 processes and one cluster of three plants at the same site, considered here as a unit and called a "facility", at 11 manufacturing facilities in four manufacturing sectors, defined by US Standard Industrial Classifications. These sectors, known to use hazardous chemicals, are manufacture of motor vehicle parts, plastics resins and products, and wood products, as well as metal coating and anodizing. Among these 16 processes and an entire facility, 15 achieved pollution prevention and two did not. The degree of achievement or non-achievement of pollution prevention is quantified by this method. Measurement of progress in pollution prevention is demonstrated for safer chemical substitution, other process change, and both. This demonstration applied to manufacturing processes in which the hazardous input chemicals are not substantially changed by chemical reaction during the manufacturing process, so input masses could be used as surrogates for creation of output hazardous emissions and wastes. This project demonstrated that there was not consistency in measures of production among the facilities and processes monitored, among similar types of products, in the same manufacturing sectors. These production measures also varied in their accuracy, and reasons are given for these differences. In order to measure progress in pollution prevention effectively, and compare results across processes, facilities and sectors, standardized, accurate measures of production level need to be developed, preferably by industry.