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With growing environmental concerns associated with gas-powered vehicles and busier city streets, micro-mobility modes, including traditional bicycles and new technologies, such as electric scooters (e-scooters), are becoming solutions. In 2018, e-scooter usage overtook other shared micro-mobility modes with over 38 million e-scooter trips taken. Concurrently, the societal concern regarding the safety of these devices is also increasing. To examine the types of injuries associated with e-scooters and bicycles, the National Electronic Injury Surveillance System (NEISS), a probability sample of US hospitals that collects information from emergency room (ER) visits related to consumer products, was utilized. Records from September 2017 to December 2018 were extracted, and those associated with powered scooters were identified. Injury distributions by age, sex, race, treatment, diagnosis, and location on the body were explored.

During a rollover accident the position of an occupant within a vehicle at the time of vehicle-to-ground contact affects the occupant's injury potential and injury mechanisms. During rollovers, the accelerations developed during the airborne phases cause an occupant to move away from the vehicle's center of mass towards the perimeter of the vehicle. The occupant is already in contact with vehicle structures during upper vehicle structure-to-ground impacts. The location and extent of the occupant-to-vehicle contacts and the times and locations at which the contacts occur depend upon a variety of factors including occupant size, initial position in the vehicle, restraint status, vehicle geometry, and rollover accident parameters. Onboard and offboard video of existing dolly rollover studies, specifically the “Malibu” studies, were examined to quantify the motion of the occupants' heads and determine the timing and locations of head contacts to the vehicle perimeter.

In this study, the occupant containment characteristics of automotive laminated safety glass in side window applications was evaluated through two full-scale, full-vehicle dolly rollover crash tests. The dolly rollover crash tests were performed on sport utility vehicles equipped with heat-strengthened laminated safety glass in the side windows in order to: (1) evaluate the capacity of laminated side window safety glass to contain unrestrained occupants during rollover, (2) analyze the kinematics associated with unrestrained occupants during glazing interaction and ejection, and (3) to identify laminated side window safety glass failure modes. Dolly rollovers were performed on a 1998 Ford Expedition and a 2004 Volvo XC90 at a nominal speed of 43 mph, with unbelted Hybrid II Anthropomorphic Test Devices (ATDs) positioned in the outboard seating positions.

Properly restraining a child in an automotive seat may require the use of a weight- and size-appropriate Child Restraint System (CRS). Proper installation of the CRS is a critical part of protecting a child during a motor vehicle collision. During a collision, child occupants sometimes exert enough force on the restraint system to generate load marks on the CRS and the vehicle restraint system. These marks are often relied upon by investigators to determine if the child occupant was properly restrained at the time of the collision. This paper is an observational study of the load marks generated from sled testing that was conducted using Hybrid III 3-year-old and 6-year-old Anthropomorphic Test Devices (ATDs). Tests were conducted with various child restraint systems that were installed in accordance with the manufacturer's recommendations as well as installed improperly. Additional tests were conducted with the ATDs without the use of a CRS.

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.

It is widely accepted that a motorcycle helmet will reduce the risk of a serious brain injury during an accident through energy dissipation. Currently, there is no literature on what happens to a motorcycle helmet after repeated significant impacts or why it cannot be re-used according to the DOT label. It is also unclear experimentally if the foam liner is permanently affected after repeated impacts. In this study, we repetitively dropped one style of DOT-approved motorcycle helmet using a drop tower system in accordance with FMVSS 218. Helmeted Hybrid III and magnesium headforms were dropped onto a flat anvil with contact to the apical region of the helmets. Strips of pressure-indicating film were placed in the mid-sagittal plane between the foam liner and the headform. Headform accelerations and head injury criterion (HIC) for the Hybrid-III headform were calculated for each drop test. There was a trend for maximum headform acceleration to increase with the number of impacts.

This study investigates the technique used and forces applied on the latch plate and buckle during typical seat belt operation and driving conditions. These techniques and forces are relevant to whether the latch plate can be partially engaged with the buckle during typical operation and whether the latch plate will dislodge during vehicle operation. In addition to studying the insertion of the latch plate, we examined the tensile forces that are applied to the latch plate and buckle during typical, non-crash driving conditions, and how these forces compare to the performance requirements established by the National Highway Traffic Safety Administration (NHTSA) as part of Federal Motor Vehicle Safety Standards (FMVSS) 209. These tensile forces are important in understanding whether the latch plate is likely to dislodge from the buckle if it is in a position of partial engagement.

Vision plays a key role in the safe and proper operation of vehicles. To safely navigate, drivers constantly scan their environments, which includes attending to the outside environment as well as the inside of the driver compartment. For example, a driver may monitor various instruments and road signage to ensure that they are traveling at an appropriate speed. Although there has been work done on naturalistic driver gaze behavior, little is known about what information drivers glean while driving. Here, we present a methodology that has been used to build a database that seeks to provide a framework to supply answers to various ongoing questions regarding gaze and driver behavior. We discuss the simultaneous recording of eye-tracking, head rotation kinematics, and vehicle dynamics during naturalistic driving in order to examine driver behavior with a particular focus on how this correlates with gaze behavior.

Test methods for vehicle safety development are either based on the movement of a vehicle into a stationary barrier or the movement of a barrier into a stationary vehicle. When deemed necessary, a two-moving-vehicle impact is approximated by modifying the impact motion between the moving and stationary objects. For example, the Federal Motor Vehicle Safety Standard (FMVSS) 214 side-impact crash test procedure [1] approximates the lateral impact of a moving vehicle into the side of another moving vehicle by using a moving barrier with wheels crabbed so that the velocity vector of the barrier is not collinear with its longitudinal axis. Such approximations are valid when the post-impact motions of the two vehicles are not to be evaluated. Similarly, the published data indicates that historic analyses of motorcycle accidents and the advancements in motorcycle safety designs have been based, in large part, on single-moving-vehicle crash tests.

One element of primary interest in the analysis and reconstruction of vehicle collisions is an evaluation of impact severity. The severity of an impact is commonly quantified using vehicle closing speeds and/or velocity change (delta-V). One fundamental methodology available to determine the closing speed and corresponding velocity change is an analysis of the collision based on a combination of the principles of Conservation of Momentum and Conservation of Energy. A critical element of this method is an assessment of the amount of kinetic energy that is dissipated during plastic structural deformation (crush) of the involved vehicles. This crush energy assessment is typically based on an interpolation or an extrapolation of data collected during National Highway Traffic Safety Administration (NHTSA) sponsored crash testing at nominal speeds of 30 or 35 mph.

Obesity is a growing problem in the general population. Recent studies have suggested a link between occupant anthropometry and injury risk in motor vehicle accidents. Adult subjects covering a range of heights, weights, and body mass index (BMI) were seated in passenger cars and asked to adjust the seat and restraint to a comfortable driving position. Differences75 in driver position and clearance measures between normal weight, overweight, and obese occupants were assessed. Occupant height was found to be a good predictor of some seating position and clearance measures, while BMI was found to be a better predictor of others. Relationships were also found relating waist circumference to measures of seating position and clearance. The results of this study are essential in developing quantitative models to investigate relationships between anthropometry and injury potential.

Federal Motor Vehicle Safety Standard No. 213 specifies requirements for child restraint systems used in motor vehicles and was first introduced by the National Highway Safety Bureau in 1971. In 1981, the standard was modified to require dynamic testing of child restraints. Over the following 21 years, Standard No. 213 was modified on numerous occasions, most recently in June of 2003. This paper outlines the history of Standard No. 213 with a discussion of the changes that have been proposed, the comments submitted to NHTSA in response to these proposed changes, and NHTSA's final decision (rule making) regarding which changes to adopt. Detailed discussion is included regarding NHTSA's May 2002 proposal to change the crash pulse, test dummies, injury criteria, and test bench required as part of the dynamic testing. The 2002 proposal also included expansion of the standard to cover child restraints for children weighing up to 65 pounds.

Crash tests of vehicles by striking deformable barriers are specified by Government programs such as FMVSS 214, FMVSS 301 and the Side Impact New Car Assessment Program (SINCAP). Such tests result in both crash partners absorbing crush energy and moving after separation. Compared with studying fixed rigid barrier crash tests, the analysis of the energy-absorbing behavior of the vehicle side (or rear) structure is much more involved. Described in this paper is a methodology by which analysts can use such crash tests to determine the side structure stiffness characteristics for the specific struck vehicle. Such vehicle-specific information allows the calculation of the crush energy for the particular side-struck vehicle during an actual collision – a key step in the reconstruction of that crash.

Certain ankylosing spondyloarthropathies such as ankylosing spondylitis (AS) or diffuse idiopathic skeletal hyperostosis (DISH) can substantially alter clinicopathologic spine biomechanics as well as injury mechanisms in rear-end motor vehicle collisions. AS is an inflammatory disease which can lead to structural impairments of the spine secondary to flowing ossification along the spinal column, including ossification across the spinal discs, facet joints, and ligaments, and it has also been associated with diffuse osteoporosis of the spine. DISH is characterized by excess bone formation along the spinal column, encompassing the annulus and forming the thickest and strongest bridging osteophytes over adjacent vertebral bodies at the level of the disc space. In both conditions the spine is mechanically stiffened and generally more kyphotic than a healthy spine.

One potential fire ignition source in a motor vehicle is the hot surfaces on the engine exhaust system. These hot surfaces can come into contact with combustible and flammable liquids (such as engine oil, transmission fluid, brake fluid, gasoline, or Diesel fuel) due to a fluid leak, or during a vehicle collision. If the surface temperature is higher than the hot surface ignition temperature of the combustible or flammable liquid in a given geometry, a fire can potentially ignite and propagate. In addition to automotive fluids, another potential fuel in post-collision vehicle fires is grass, leaves, or other vegetation. Studies of hot surface ignition of dried vegetation have found that ignition depends on the type of vegetation, surface temperature, duration of contact, and ambient conditions such as temperature and wind speed. Ignition can occur at surface temperatures as low as 300 °C, if the vegetation is in contact with the surface for 10 minutes or longer.

The likelihood of a front seat occupant sustaining a femoral shaft fracture in a frontal crash has traditionally been assessed by an injury criterion relying solely on the axial force in the femur. However, recently published analyses of real-world data indicate that femoral shaft fracture occurs at axial loads levels below those found experimentally. One hypothesis attempting to explain this discrepancy suggests that femoral shaft fracture tends to occur as a result of combined axial compression and applied bending. The current study aims to evaluate this hypothesis by investigating how these two loading components interact. Femoral shafts harvested from human cadavers were loaded to failure in axial compression, sagittal plane bending, and combined axial compression and sagittal plane bending.

Occupant ejection may occur during planar and rollover collisions. These ejections can be associated with serious/fatal injuries. Occasionally, occupants will allege that they were wearing a seatbelt immediately before the ejection occurred. Some accident investigators have opined that a seatbelt became disengaged due to collision forces and/or occupant interactions, leaving the occupant essentially unrestrained and exposed to ejection from the vehicle. We present three case studies of collisions with documented seatbelt disengagement at or during the collision, as well as three controlled tests. The release of the seatbelt was always associated with dire consequences for the occupant's outboard upper extremity. Evidence of seatbelt webbing interaction with the occupant was always evident, and the interaction of the belt with the vehicle interior trim was also apparent.

There is a paucity of data regarding the potential for pediatric cervical spine injury as a result of acceleration of the head with no direct impact during automotive crashes. Sled tests were conducted using a 3-year-old anthropomorphic test device (ATD) to investigate the effect of restraint type and crash severity on the risk of pediatric inertial neck injury. At higher crash severities, the ATD restrained by only the vehicle three-point restraints sustained higher peak neck tension, peak neck extension and flexion moments, neck injury criterion (Nij) values, peak head accelerations, and HIC values compared to using a forward-facing child restraint system (CRS). The injury assessment reference values (IARVs) for peak tension and Nij were exceeded in all 48 and 64 kph delta-V tests using any restraint type.

Crash tests of vehicles by striking deformable barriers are specified by Government programs such as FMVSS 214, FMVSS 301 and the Side Impact New Car Assessment Program (SINCAP). Such tests result in both crash partners absorbing crush energy and moving after separation. Compared with studying fixed rigid barrier crash tests, the analysis of the energy-absorbing behavior of the vehicle side (or rear) structure is much more involved. Described in this paper is a methodology by which analysts can use such crash tests to determine the side structure stiffness characteristics for the specific struck vehicle. Such vehicle-specific information allows the calculation of the crush energy for the particular side-struck vehicle during an actual collision – a key step in the reconstruction of that crash.

Low-speed sideswipe collisions between tractor-semitrailers and passenger vehicles can result in large movements and extensive areas of visible damage to the passenger vehicle. However, depending on the specifics of the collision, the resulting crash pulse may be extended, and the vehicle accelerations correspondingly low. Research regarding the impact environment and resulting injury potential of the occupants during these types of impacts is limited. Five full-scale crash tests utilizing a tractor-semitrailer and a passenger car were conducted to explore vehicle responses during these types of collisions for both the passenger car and the tractor-trailer. The test vehicles included a loaded van semitrailer pulled by a tractor and three identical mid-sized sedans. Instrumentation on the sedans included accelerometers and rotational rate sensors, and the vehicle and occupant kinematics were recorded using onboard and off-board real-time and high-speed video cameras.