Citation

Minahan DJ, O'Day J. HSRI Res. Rev. 1977; 8(3): 1-16.

Copyright

(Copyright © 1977, University of Michigan Highway Safety Research Institute)

DOI

unavailable

PMID

unavailable

Abstract

To estimate the current national frequency of underride collisions and to assess the effectiveness of underride guards used on large trucks and tractor-trailers, HSRI examined all fatal car-truck collision cases in Michigan (1972-1976) and Texas (1975-1976). The impact configurations and degree of underride were established by examining the police accident reports and photos and, when possible, interviewing the investigating police officers. Relative impact speed was estimated for each case. An estimate based on the multi-year data puts the current number of fatal car-into-turck underride collisions at 456 nationally. This includes 261 rear impacts and 195 side impacts. An estimate based on only the 1976 data puts the current national total at 571. This includes 308 rear impacts and 263 side impacts. Of the 181 car-truck/trailer fatal crashes studied, underride occurred in more than 90 percent of the rear collisions and in 75 percent of the side collisions. Impact speed was greater than 30 mph in 77 percent of the cases. Among the study conclusions: the frequency of such collisions would be reduced if trucks and trailers were made more conspicuous, and the frequency of underrides in car-into-truck collisions would be reduced if trucks and trailers were equipped with improved underride guards.