The Pipeline and Hazardous Materials Safety Administration's (PHMSA) Office of Hazardous Materials Safety (OHMS) maintains the Hazardous Materials Incident Reporting System (HMIRS), a database of information regarding incidents involving hazardous materials. Lack of guidance and definitions to be used in providing data for the financial consequences and under-reporting by the regulated community seriously compromises the credibility of the cost fields of the HMIRS database. A statistical modeling approach was examined in this paper in order to determine if it could be useful in providing improved estimates of the total annual financial consequences associated with hazardous material incidents. A stratified sample of 500 hazardous material incidents occurring between November 1, 2002 and October 31, 2003 was selected, and the carrier contacts listed in the HMIRS database for each incident were called and asked to provide more detailed cost information regarding the incident for five cost categories. Stepwise regression analysis was used to determine significant predictor variables for several cost components within each of the strata. The resulting models were used to predict the actual costs of each incident in the HMIRS database for the period of study and estimated incident costs were summed to obtain an estimate of the total annual hazardous material incident costs. The HMIRS reported costs were $49.8 million for period of study, while the stratified regression method produced an estimated total annual hazardous material incident cost of $77.7 million, with a 95 percent confidence interval ranging from $66.6 million to $88.8 million.
Abstract