Transportation firms reported more than 17,700 hazardous materials incidents in 2001.1 These incidents resulted in 7 deaths and 143 injuries, compared with annual averages of 21 deaths and 445 injuries between 1991 and 2001. During that decade, the number of reported hazardous materials incidents in-creased (figure 79). However, much of the increase may be attributed to improved reporting and an expansion of reporting requirements2 (see box).
Highway vehicles transported 56 percent of the tons of hazardous materials shipped in 1997 . Between 1991 and 2001, 62 percent of the injuries and 53 percent of the fatalities attributed to hazardous materials were the result of highway incidents. Fatal hazardous materials transportation incidents in other modes tend to be infrequent. After a DC-9 aircraft crashed in Florida in 1996 killing 110 people, the National Transportation Safety Board found that the crash was caused by ignited oxygen leaking from improperly stored oxygen generators . With the exception of occasional spikes, injuries generally declined in the 1990s, especially from highway incidents (figure 80). Of the 926 injuries attributed to rail incidents in 1996, 787 resulted from chlorine released when a train derailed in February in Alberton, Montana .
Environmental contamination can occur as the result of hazardous materials incidents, but data are not routinely collected on the extent of the damage. Their environmental impacts will depend on the concentration and type of material spilled, the location and volume of the spill, and exposure rates.
1. National Transportation Safety Board, NTSB Report AAR-97/06, Docket No. DCA96MA054.
2. U.S. Department of Transportation, Bureau of Transportation Statistics, and U.S. Department of Commerce, U.S. Census Bureau, 1997 Commodity Flow Survey, Hazardous Materials (Washington, DC: December 1999).
3. U.S. Department of Transportation, Researchand Special Programs Administration, personal communication, May 2003.
1 A reported incident is a report of any unintentional release of hazardous materials while in transportation (including loading, unloading, and temporary storage). It excludes pipeline and bulk shipments by water, which are reported separately.
2 Incident reporting requirements were extended to intrastate motor carriers on Oct. 1, 1998, which may partly explain the subsequent increased volume of reports. Beginning in April 1993, there was a sharp improvement in reporting of incidents by small package carriers.