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When investigating a vehicle crash, the issue of seatbelt usage is frequently part of the information needed to perform an occupant kinematics or injury analysis. A physical inspection of the vehicle is the preferred method to investigate seatbelt usage. However, if the vehicle is no longer available, or the condition has changed since the time of the crash, preventing analysis of seatbelt usage by an occupant, the investigators must rely on other available evidence to assess occupant seatbelt usage. This would typically include a review of the police report, scene or early photographs of the vehicle, physical marks on the occupant in medical records and statements from witnesses. More recently, event data recorders (EDR) can provide data regarding seatbelt status for front seat occupants, and occasionally, rear seat occupants. However, the EDR data must have been previously recovered or the vehicle must be available.

Observations made during forensic automotive crash investigations have identified instances of non-zero, post-crash speedometer readings and created questions as to the validity of the indicated speed relative to the vehicle speed at impact. Previously published work has addressed many issues related to the reliability of non-zero, post-crash speedometer readings identified in vehicles as well as motorcycles. Much of this work established criteria that related the reliability of the post-crash needle position to the design of the stepper motor that controls the needle. Part of this criteria is related to the static torque associated with the speedometer needle shaft rotation due to outside (crash) forces. The published criteria were evaluated in staged crash tests which investigated the ability to maintain needle position under longitudinal and lateral forces after an electrical power loss.

The National Institute for Occupational Safety and Health (NIOSH), in cooperation with the Canadian Forces Health Services Group Headquarters, U.S. Army Tank-Automotive and Armaments Command (TACOM), and the Ministry of Health & Long-Term Care, Ontario (Canada), conducted a test program to evaluate the capability of mobile restraint systems to protect occupants in the patient compartment of an ambulance. This paper focuses on the vehicle chassis behavior and acceleration pulses as seen in each test conducted to support the program. This program consisted of testing one Type I ambulance mounted on a Ford F-350 truck chassis (1994 vintage), and three Type III ambulances mounted on Ford E-350 van chassis (two 1993, and one 1999 vintage). A vehicle-to-vehicle side impact test was conducted using the Type I ambulance with a targeted change in velocity of 27.4 kph (17 mph). A 1984 Chevrolet Sierra 2500 was the impacting vehicle for the side test.

Over the past 40 years since seat belts were first required in the front seats of passenger cars in the United States, numerous features have been incorporated in these systems. One such feature is the web loop. Vehicles manufacturers have used web loops in numerous vehicles over the years and have indicated that they modify kinematic and/or absorb energy. A web loop consists of a length of seat belt webbing held in place with a pattern of stitches designed to tear out, or rip, at a predetermined load. This concept is similar to the fall protection lanyards or load limiting parachute risers, both of which are designed to reduce shock loading on the user. While generally these systems are tested using a slow application of force, in a crash, the loads are applied more rapidly. This has presented a question as to how the deployment force varies when the stitching is loaded more rapidly.

Rollover crashes, while less frequent than other types of crashes, result in a disproportionately large percentage of the fatal and serious injuries sustained by motor vehicle occupants, including children (Howard, 1995; Esterlitz, 1989). Howard's analysis of U.S. National Automotive Sampling System General Estimates System and the Fatal Analysis Reporting System databases from 1995 through 1999 found that while only 2.2% of children were subjected to rollover crashes, these crashes resulted in 1,832 (28%) of the 6,570 child passenger fatalities. With the transition by U.S. families from traveling in primarily passenger cars to minivans and sport utility vehicles, there is expected to be a significant increase in the exposure of rollover crashes to child occupants due to the higher frequency of rollover crashes with these vehicles (Howard, 2003; Rivara, 2003; Malliaris, 1987).

The authors have analyzed hundreds of real world crashes and simulated crash tests involving child safety seats. These child safety seats were involved in impacts with a variety of principle directions of force and changes in velocity. Indications of loading of the child safety seat seen during inspections were used by the authors to draw conclusions relative to how the child safety seat was used and loaded during the collision. It was hypothesized that if these marks were created due to loading in the subject crash as expected, that a test program with a similar principle direction of force and load levels could be conducted and the test seats would exhibit similar loading marks. For each of the cases discussed, the authors have inspected the actual child seat involved in a crash and then conducted a test or tests on representative sample(s) of the same type of child safety seat. Following the tests, these child safety seats were inspected for loading marks and comparisons were made.

Inadequately restrained cargo is a problem in a wide range of vehicles, from passenger cars to heavy trucks. In a crash, the force needed to restrain the cargo is many times the weight of the cargo itself. In a passenger vehicle this means that the barrier between the cargo and the occupants must be capable of preventing the cargo from entering the passenger compartment. In heavy trucks, cargo restraints are generally used to prevent the shifting of cargo that could affect the stability of the truck and to keep the cargo on, or in, the truck during normal driving maneuvers. A somewhat unique problem occurs in the armored security vehicle. These vehicles are often used to transport very heavy, dense, valuable cargo. More specifically, this cargo is often coin and/or boxes containing paper currency. In many cases this cargo, which may exceed 2268 kilograms (5000 pounds), is carried in the same compartment as personnel.

There are many factors that must be considered when designing a restraint system. The way the components function as a system and the design of the system's components are among these factors. While there are several tests required by the US Federal Motor Vehicle Safety Standards, not all factors are addressed. This paper will address the resistance of a seat belt buckle to accidental or inadvertent release. The test procedure deals with the design of the buckle only and does not consider other important factors such as placement or shielding. There have been numerous reports where occupants are found unrestrained following a crash even though evidence, such as witness statements, use and custom or clear physical findings, indicates the occupant was belted. It is believed by many that some of these cases are the result of inadvertent buckle release.

There has been very limited research on the biomechanics of occupant safety in the ambulance environment. Occupant protection or crash testing safety standards for these unique vehicles are lacking in the United States. Recent studies have identified ambulances as high risk passenger transport vehicles. This study was conducted to identify some of the occupant safety hazards in the ambulance environment and to determine the efficacy of some countermeasures to mitigate ambulance occupant injury. Accelerator sled testing of the ambulance rear patient compartment (ambulance box or rear cabin) with Anthropomorphic Test Devices was conducted under frontal impact conditions with a target sled pulse was 26 G and 30 mph. The ambulance box was configured with instrumented and uninstrumented Anthropomorphic Test Devices positioned as in the real world environment.

This exploratory study investigated the effect of cognitive workload on manual lap belt usage in automatic restraint systems consisting of a passive motorized shoulder belt and a separate manual lap belt. Previous observational studies showed that, while these types of passive automatic restraint systems increased shoulder belt usage, occupants frequently did not engage the manual lap belt. This omission put the occupants at a significantly increased risk of injury in a crash. These studies also suggest that forgetfulness was one of the main reasons that occupants did not engage the manual lap belt. The objective of this study was to quantify manual lap belt usage with this type of automatic restraint system under varying cognitive workloads. Ten subjects participated in two testing sessions consisting of a low and high cognitive workload. During each test session, the subjects drove around a pre-defined course where they exited the vehicle at five locations to perform specific tasks.