Literature Review and Framework for Identifying Seat Belt Misuse and Misrouting in Frontal Collisions

<div class="section abstract"><div class="htmlview paragraph">The effect of seat belt misuse and/or misrouting is important to consider because it can influence occupant kinematics, reduce restraint effectiveness, and increase injury risk. As new seatbelt technologies are introduced, it is important to understand the prevalence of seatbelt misuse. This type of information is scarce due to limitations in available field data coding, such as in NASS-CDS and FARS. One explanation may be partially due to assessment complexity in identifying misuse and/or misrouting. An objective of this study was to first identify types of lap-shoulder belt misuse/misrouting and associated injury patterns from a literature review. Nine belt misuse/misrouting scenarios were identified including shoulder belt only, lap belt only, or shoulder belt under the arm, for example, while belt misrouting included lap belt on the abdomen, shoulder belt above the breasts, or shoulder belt on the neck. Next, the literature review identified various methods used to assess misuse/misrouting including testimonies and physical evidence on the occupant (i.e., belt marks/injury pattern) and on the vehicle interior and/or restraint system (i.e., loading marks). The literature review also highlighted the scarcity of test data on this topic, which may be beneficial to help guide technologies used to address and detect such scenarios.</div><div class="htmlview paragraph">A surrogate study with a female volunteer was conducted for each of the nine belt misuse/misrouting scenarios identified from the literature review. The webbing lengths and angles at the hardware were measured. The results provide a first step in documenting evidence that could be part of a crash investigation. Additional studies with various size occupants are suggested, in conjunction with physical and/or mathematical simulation tests.</div><div class="htmlview paragraph">Based on the literature review, a comprehensive and integrated framework to determine belt misuse/misrouting was summarized. The framework is based on information from police and accident vehicle investigation, and medical and radiology records. It also highlighted the need to measure webbing lengths and seat belt hardware angles that can be used in conjunction with surrogate studies and dynamic tests. Technologies such as video footage from in-vehicle cameras have the potential to provide additional data.</div></div>