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Lower extremity injuries resulting from motor vehicle crashes are both frequent and associated with considerable long-term impairment. Deformation of a vehicle's occupant compartment resulting in intrusion into the foot area is often cited as a source of many of these injuries. Similarly, collisions involving only a portion of a vehicle's front structure are typically said to produce greater intrusion than fully engaged crashes. The relationship between occupant compartment intrusion and the risk of lower extremity injuries was examined through a series of offset frontal crash tests of 1984-89 Oldsmobile Cieras. Results from both car-to-car and car-to-barrier test crashes with instrumented dummies confirm that there is a relationship between occupant compartment deformation and the loads acting on the lower extremities of vehicle occupants, even when crash severity has been controlled.

A review of 39 driver fatalities in 1990-93 cars with air bags from the National Accident Sampling System indicated most of these fatalities were due to causes unrelated to frontal air bag performance. Two-thirds occurred in side-impact or rollover crashes, in which air bag effectiveness is limited; of 15 frontal crash fatalities, 6 died of causes unrelated to the frontal impact and 5 in cars with severe intrusion. The remaining four fatalities, three of whom were unbelted, were in moderate to high severity crashes which could have been survivable; however the deploying air bags, instead of protecting, probably contributed to the fatal injuries. A similar review of 12 fatalities of unbelted drivers in cars without air bags revealed 3 could have been prevented by air bags, but 4 were in crashes that could have put them in position to be injured by the air bag.

Seat belt use laws in New York, Michigan, New Jersey, and Illinois reduced front seat occupant fatalities by an estimated 16, 10, 6 and five percent respectively, during the months in 1985 they were in effect. Only the reduction for New York was statistically significant, but the similarity between the pattern of fatality reductions and the pattern of increases in seat belt use lends credibility to the estimates. Each reduction was less than expected given the known effectiveness of seat belts and the observed rates of use in noncrash populations, suggesting again that seat belt use laws are less successful in increasing belt use among those who are more likely to be in crashes. Pedestrian fatalities were unaffected by the laws, indicating that “risk compensation” was not a factor modifying the success of the laws.

Using data from the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) for1995-96, this study updates previous analyses of driver fatalities in airbag-equipped vehicles in the NASS/CDS database for 1989-93 and 1989-94. A total of 59 cases of frontal crashes of airbag-equipped vehicles with driver fatalities were identified in these 8 years of NASS/CDS data, but in 9 cases the fatalities were not related to the impacts (e.g., fire, medical condition). Vehicle intrusion was the cause of the fatal injuries in 27 cases, and 7drivers died from injuries sustained when they were either partially or totally ejected from their vehicles. There was one case in which the airbag did not deploy, although the crash conditions indicated it should have. One driver died from contact with a nonintruding vehicle surface, and the causes of the fatal injuries in 5 cases were unknown.

Automobile safety has improved since the 1960s, mostly because of improved vehicle structures and restraint systems. Another round of revolutionary change is promised by advanced information technologies, but it's unlikely that all of these will improve safety. In particular, many of these technologies change the driving task, and it's critical to understand how drivers respond to the changes because the responses may enhance or counteract any potential safety benefits. This paper will discuss what is necessary to predict driver response.

Despite extensive media coverage to the contrary, mismatches among cars, utility vehicles, and pickups in crashes is not a big problem from a societal perspective. On the other hand, if you are riding in a small car that is about to be hit by a big utility vehicle, then the problem looms large. Crash compatibility has attracted a lot of attention lately because utility vehicles have become so popular. The concern is that their designs pose a threat to people riding in smaller cars. But the fact is, two-vehicle collisions between cars (including passenger vans) and utility vehicles or pickups account for only about 15 percent of all car occupant deaths. As a result, countermeasures that focus on making utility vehicles and pickups more crash compatible, however appropriate, can have only small effects on crash injuries and fatalities. On the other hand, improvements in crashworthiness not only reduce crash incompatibilities but also protect across a wider spectrum of crashes.

Since 1995, the Insurance Institute for Highway Safety (IIHS) has evaluated the crashworthiness of more than 120 new vehicle models in a 64 km/h (40 mi/h), 40 percent offset deformable barrier crash test. The offset test is especially demanding of the vehicle structure, requiring only 40 percent of the vehicle width to manage the crash energy. Many of the models originally tested have been redesigned and retested, with the majority producing better structural performance than their predecessors. Critics of such testing have suggested that these tests are forcing vehicle stiffness too high for compatibility with other vehicles and other crash modes. IIHS has studied the relationship between vehicle mass, stiffness, and front-end length to the structural rating in the offset test.

The occupants of passenger vehicles struck in the side by another vehicle are more likely to be fatally injured than are occupants of the striking vehicle. The risk of fatality in a side-struck car is higher still when the striking vehicle is a pickup or utility vehicle rather than a passenger car of the same mass. This suggests there are other factors inherent to pickup and utility vehicle design in addition to mass that contribute to this increased risk. In this paper, results are presented from a series of six 90-degree, front-to-side crash tests conducted with both vehicles moving. The side-struck vehicle, a Mercury Grand Marquis with a BioSID (biofidelic side impact dummy) in the driver position, was moving at 24 km/h (15 mi/h) in all tests.