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Three years of data from the Large Truck Crash Causation Study (LTCCS) were analyzed to identify accidents involving heavy trucks (GVWR >10,000 lbs.). Risk of rollover and ejection was determined as well as belt usage rates. Risk of ejection was also analyzed based on rollover status and belt use. The Abbreviated Injury Scale (AIS) was used as an injury rating system for the involved vehicle occupants. These data were further analyzed to determine injury distribution based on factors such as crash type, ejection, and restraint system use. The maximum AIS score (MAIS) was analyzed and each body region (head, face, spine, thorax, abdomen, upper extremity, and lower extremity) was considered for an AIS score of three or greater (AIS 3+). The majority of heavy truck occupants in this study were belted (71%), only 2.5% of occupants were completely or partially ejected, and 28% experienced a rollover event.

This paper explores tire placement with given tread depths on vehicles from two distinct perspectives. The first area explored is an analysis of crash data recently reported by the National Highway Traffic Safety Administration (NHTSA). In this report, thousands of tire-related crashes were investigated where the tread depth and inflation pressure were logged for each tire and assessments were made as to whether tire condition was a factor in the crash. The analysis of the data shows that in regards to accident causation, it is not statistically significant which axle has the deepest tread. What is significant is that a tread depth at or below 4/32″ anywhere on the vehicle leads to an increased rate of crashes. To understand the physics implied by the NHTSA data, a study was performed on how the placement of tires of various tread depths affects the steering, handling, and braking performance of a modern sport utility vehicle.

Inadvertent vehicle movement incidents, in which a vehicle rolls away after the driver has exited, may occur in automatic transmission vehicles as a result of environmental, vehicular, and/or driver factors. Some explanations have focused on claimed potential malfunctions or design flaws in the vehicle's console shift mechanism or in the automatic transmission itself. However, growing evidence suggests that driver errors unrelated to vehicle design may in fact be the primary cause of many inadvertent vehicle movement incidents. The present research extends previous work on driver gear-shifting behaviors and vehicle egress by conducting more in-depth analyses of data collected by Harley et al. (2008).

The process of design inherently involves consideration of risk trade offs; intervening to reduce one risk often increases another. In addition to creating a design for the intended function of the product, a rational process of risk management involves prediction of risk through design analysis, statistical evaluation of the history of similar products, and potentially multidisciplinary teams to address diverse causes of risk. As a case study, this paper examines the benefits of using one class of fire retardant to reduce risk of vehicle fire injuries and the countervailing health risk due to increased quantities of fire retardants released in the interior environment. Data sources for fire and health risk were researched and interpreted for use in the analysis. Information needed to reduce the uncertainties in the risk predictions are identified for future refinements to the conclusions.

Police accident reports (PARs) of motor vehicle collisions typically include information regarding occupant restraint use. It has been suggested that PARs overestimate restraint use. Previous studies comparing PAR restraint usage with that determined during a NASS/CDS in-depth investigation found agreement in approximately 90% of cases. The accuracy of PAR-reported restraint usage for outboard vehicle occupants was compared to that determined by NASS/CDS investigators as a function of injury severity and crash type. Restrained occupants were more likely to be identified correctly in the PAR, and unrestrained occupants were more likely to be accurately identified as injury severity increased. Differences in the accuracy of PAR-reported restraint usage rates for different crash types were small.

Fires originating in large trucks can be significant in terms of both the potential for personal injury or death and the potential for substantial economic loss of the vehicle and its cargo. This analysis examines the large trucks involved in fire incidents and the causes of the fires by examining the National Automotive Sampling System (NASS/GES), the Large Truck Crash Causation Study (LTCCS), and the Fatality Analysis Reporting System (FARS). In this report we compare the rate of post-collision fire observed in these databases, analyze the reasons for differences in and describe the circumstances of large truck fires as reported in the LTCCS.

Objective: To provide an understanding of the scope of the major sources of vehicle fire data, the questions they were intended to answer, and how issues of definition, inclusion, and quality can affect the conclusions obtained. The National Highway Traffic Safety Administration's (NHTSA's) Fatality Analysis Reporting System (FARS), by definition, focuses on fatal accidents. NHTSA also maintains the National Automotive Sampling System (NASS) General Estimates System (GES).These systems capture data on roadway accidents that resulted in injury, fatality or property damage and which were reported to police. The GES system is based upon data recorded in the police accident report. In addition, some databases of police accident reports are publicly available. The U.S. Fire Administration's (USFA's) National Fire Incident Reporting System (NFIRS) is used by fire departments to document details about all types of fires.

The subject of whether roof deformation in and of itself causes occupant injury in rollover accidents has been emotionally, scientifically and legally contested for decades. Since the publication of the earliest scientific research on the issues of automobile roof strength and non-ejected passenger protection in rollover crashes, the two views have been generally diametrically opposed to one another, and the debate continues. In order to gain perspective on the subject, the question must be answered as to how effective past and current automotive vehicle roof structures, designed to meet current government and industry standards, have proven to be in protecting vehicle occupants during real-world accidents involving the rollover of the vehicle they occupy.

Recently there has been increasing interest in stationary vehicle fires (SVF) and the safety of vehicles parked in garages. This interest has grown out of allegations by insurance companies that garage fires, some of which spread to other parts of the residence and cause considerable damage and/or injuries, may be caused by vehicles, and hence the vehicle manufacturer should be liable for damages. Data from the National Fire Incidence Reporting System (NFIRS) 1999-2002 were used to study the involvement of motor vehicles in garage fires and to compare the risk of injury and fatality in post collision fuel fed fires (PCFFF) to risk of fatality in garage fires. This paper explores the role of both vehicles and other causes in garage fires. It is found that only 4.4% of garage fires in the US, or approximately 1,200 annual fires, are of the type that could possibly be related to vehicle design or maintenance.

The purpose of this study was to analyze real world crash data to determine whether airbags cause more severe injuries than they prevent and which types of injuries they cause. Using data from the National Accident Sampling System Crashworthiness Data System (NASS CDS), we examined passenger vehicles involved in frontal collisions for calendar years 1995-2003. We found that 99% of airbag-induced injuries to front outboard occupants are minor or moderate, regardless of the occupants' belt use. Belted occupants are 4 times more likely to sustain an AIS3+ injury (serious, severe, critical, or maximum) from any injury source compared to occupants with an airbag-induced injury; the risk of AIS3+ injury from any source is even higher for unbelted occupants. The evidence suggests that airbags do indeed mitigate severe injury.