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This study, which is an extension of an earlier study, examined an additional 64 frontal crashes of airbag-equipped vehicles in the 1997-98 National Automotive Sampling System Crashworthiness Data System (NASS/CDS) in which the driver died. The principal cause of death in each case was determined based on an examination of the publicly available case materials, which primarily consisted of the crash narrative, the injury/source summary, and photographs of the crashed vehicle. Results were consistent with the earlier analyses of the 1990-96 NASS/CDS files. In the combined data set (1990-98), gross deformation of the occupant compartment was the leading cause (42 percent) of driver deaths in these 116 frontal crashes. The force of the deploying airbag (16 percent) and ejection from the vehicle (13 percent) also accounted for significant portions of the driver deaths in these frontal crashes. There continues to be little or no evidence that airbags deploy with too little energy.

The Insurance Institute for Highway Safety (IIHS) is investigating small overlap crash test procedures for a possible consumer information program. Analysis of real-world small overlap crashes found a strong relationship between serious head and chest injuries and occupant compartment intrusion. The main sources of serious head injuries were from the A-pillar, dash panel, or door structure, suggesting head trajectories forward and outboard possibly bypassing the airbag. Chest injuries mainly were from steering wheel intrusion and seat belt loading. In developing this program, two test dummies were evaluated for predicting occupant injury risk: midsize male Hybrid III and THOR. In the collinear small overlap crash tests conducted here, results from the two dummies were similar. Both predicted a low risk of injury to the head and chest and sometimes a high risk of injury to the lower extremities. Head and torso kinematics also were similar between dummies.

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.

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.

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.

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.

Laws requiring seat belt use have had some limited success in reducing occupant fatalities. However, fatality reductions have been considerably less than expected from the reported increases in belt use rates because belt use by those in crashes has not increased to the same extent. Occupants most likely to be in serious crashes are least likely to increase their use of belts in response to laws. In addition, many involuntary belt users comply with belt use laws by wearing their belts incorrectly, in ways that greatly reduce their effectiveness, and many in front seats who wear belts in response to laws are susceptible to being impacted in crashes by unbelted rear seat occupants. The incomplete success of belt use laws does not reduce their importance as a countermeasure, but does reinforce the importance of providing automatic (“passive”) protection to vehicle occupants as an alternative or supplementary countermeasure.

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.

In 2012, the Insurance Institute for Highway Safety (IIHS) began a 64 km/h small overlap frontal crash test consumer information test program. Thirteen automakers already have redesigned models to improve test performance. One or more distinct strategies are evident in these redesigns: reinforcement of the occupant compartment, use of energy-absorbing fender structures, and the addition of engagement structures to induce vehicle lateral translation. Each strategy influences vehicle kinematics, posing additional challenges for the restraint systems. The objective of this two-part study was to examine how vehicles were modified to improve small overlap test performance and then to examine how these modifications affect dummy response and restraint system performance. Among eight models tested before and after design changes, occupant compartment intrusion reductions ranged from 6 cm to 45 cm, with the highest reductions observed in models with the largest number of modifications.

The current study estimates about 5 percent of the U.S. female population sits closer than 10 inches from the steering wheel; 35 percent for the smallest 10 percent of the female population. Of the females sitting closer than 10 inches, 66 percent sit within 9-10 inches, and 17 percent sit within 8-9 inches. In a separate study, drivers sitting within 9-10 inches were able to increase this distance to 10 inches or more and still drive comfortably in a number of cars by making a few minor seating adjustments.

This paper examines the effects that downsizing has had on occupant injury. Statistical models are derived which demonstrate the relative risks associated with downsized cars and restraint use. Then actual occupant injuries are analysed to show how the total pattern of occupant injuries changes with downsizing. Each additional thousand pounds of vehicle mass decreases the odds of a driver injury in a crash by 34 percent when the driver is not restrained. For restrained drivers, this decrease is 25 percent per thousand. Restraint use further decreases the odds of a driver injury by two-thirds. To gain the same reduction in injury odds afforded the belted driver of a 2500 pound passenger car, the unbelted driver requires a 4325 pound car. For unrestrained occupants, the instrument panel, steering assembly and windshield (in frontal impacts) are the most frequent sources of injury.

Data on deaths of car occupants during the calendar year 1975 were obtained from the National Highway Traffic Safety Administration's Fatal Accident Reporting System, and national vehicle registration counts were obtained from R. L. Polk National Profile as of July 1, 1975. Occupant deaths per 10,000 registered cars in the 1971 through 1974 model years were examined by vehicle size. Occupant death rates generally increase as car size decreases. The relationship between smaller cars and increased deaths is especially pronounced in frontal crashes, and in car into other vehicle crashes. Because of this, increased occupant crash protection in frontal crashes-such as provided by air bags and passive seat belts-could substantially reduce much of the disadvantage presently faced by occupants of small cars.