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High-intensity discharge (HID) headlamps are increasingly being employed in place of incandescent headlamps for automotive forward light systems. While the post-impact analysis of incandescent bulbs and filaments to determine the power state at impact is a mature field, there is little information currently available in the literature that can be used to determine if an HID headlamp was powered at the time of impact. HID headlamps differ significantly both in architecture and operation compared to incandescent headlamps; the light is produced by passing electrical current through a gas and generating a luminous arc, rather than by resistive heating of an incandescent filament. Though the filament examination techniques often used by accident investigators cannot be directly applied to HID lamps, the unique features of these lamps provide opportunities for new methods. This paper presents the results of stationary impact tests performed on a representative HID lamp.

Approximately 600,000 fatalities occur each year as a result of pedestrians being impacted by motor vehicles (World Bank, 2008). Previous studies (Heller et al., 2009) have utilized databases such as the National Inpatient Sample (NIS) to gain a more thorough understanding of the common injury patterns that occur in real-world traffic collisions involving pedestrians in the United States. The NIS contains records on five to eight million hospital stays annually and provides a wealth of information regarding injuries to hospitalized pedestrian casualties in the U.S. Because of the large number of applicable records in the NIS and the randomized sampling procedure, the data can be used to complete analyses that are not possible with smaller databases such as the Pedestrian Crash Data Study (PCDS), which is not intended to be statistically representative of pedestrian crashes in general.

Over half of the 1.2 million annual traffic fatalities worldwide are pedestrians struck by motor vehicles [ 1 ]. Medical databases, such as the National Inpatient Sample (NIS), have been utilized to ascertain injury patterns in the general population of injured pedestrians [ 2 - 3 ]. However, the authors are not aware of any studies investigating how factors, such as physical impairments, intoxication, and pre-existing medical implants (e.g. hip replacement, artificial knee, etc.) affect the prevalence of pedestrian accidents or injury outcomes. Five to eight million inpatient hospitalization records are included in the NIS annually, and this large sample size allows for analyses that are not possible with smaller data sets on pedestrian injuries. The current study utilizes the NIS to evaluate how several factors such as blindness, deafness, intoxication, and pre-existing medical implants affect injury patterns when compared to the general population of hospitalized pedestrians.

The risk of sustaining injury in side collisions is correlated to collision severity as well as other factors such as restraint usage and occupant position relative to the impact. The most recent National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) data available (1997 to 2007) were analyzed to identify accidents involving passenger vehicles that have experienced an impact with a principal direction of force (PDOF) either between 8:00 and 10:00 or between 2:00 and 4:00, indicating a side impact collision. The Abbreviated Injury Scale (AIS) was used as an injury rating system for the involved vehicle occupants who were at least sixteen years old and were seated in the outboard seating positions of the front row. These data were further analyzed to determine injury risk based on resultant delta-V, restraint system use, and occupant position relative to the impact.

The risk of sustaining injury in frontal collisions is correlated to collision severity as well as other factors such as restraint usage and airbag deployment. Eleven years (1997 to 2007) of National Automotive Sampling System (NASS) data from the Crashworthiness Data System (CDS) were analyzed to identify accidents involving passenger vehicles that have experienced an impact with a principal direction of force (PDOF) between 11:00 and 1:00, indicating a frontal collision. The Abbreviated Injury Scale (AIS) was used as an injury rating system for the involved vehicle occupants who were at least sixteen years old and were seated in the outboard seating positions of the front row. These data were further analyzed to determine injury risk based on factors such as delta-V, restraint system use, and airbag deployment. Each body region (head, face, spine, thorax, abdomen, upper extremity, and lower extremity) was considered separately.

Previous studies have suggested injury assessment reference values (IARVs) for lower neck injury based on scaled upper neck values. This study developed independent flexion and extension IARVs for the lower neck by matching Anthropomorphic Test Device (ATD) data to impact-tested post-mortem human subjects (PMHSs) with mid- to low-cervical spine injuries. Pendulum and sled tests with Hybrid III midsize male and small female ATDs were run under conditions mimicking those of published PMHS torso drop-sled tests and other PMHS studies. Measurements included upper and lower neck forces and moments, head acceleration, head rotation rate, and head/neck angles for the pendulum tests. Rear impacts corresponding to rigid seatback tests without a head restraint produced lower neck extension moments that increased dramatically with test severity, as measured by increasing delta-V and/or decreasing pulse duration.