The Risk of Whiplash Injury in the Rear Seat Compared to the Front Seat in Rear Impacts

Since 1996 the NHTSA has warned of the airbag deployment injury risk to front seated children and infants, during frontal impact, and they have recommended that children be placed in the rear seating areas of motor vehicles. However, during most rear impacts the adult occupied front seats will collapse into the rear occupant area and, as such, pose another potentially serious injury risk to the rear seated children and infants who are located on rear seats that are not likely to collapse. Also, in the case of higher speed rear impacts, intrusion of the occupant compartment may cause the child to be shoved forward into the rearward collapsing front seat occupant thereby increasing impact forces to the trapped child. This study summarizes the results of more than a dozen actual accident cases involving over 2-dozen rear-seated children, where 7 children received fatal injuries, and the others received injuries ranging from severely disabling to minor injury. Types of injuries include, among others: crushed skulls and brain damage; ruptured hearts; broken and bruised legs; and death by post-crash fires when the children became entrapped behind collapsed front seat systems. Several rear-impact crash tests, utilizing sled-bucks and vehicle-to-vehicle tests, are used to examine the effects of front seat strength and various types of child restraint systems, such as booster seats and child restraint seats (both forward and rearward facing), in relation to injury potential of rear seated children and infants. The tests utilized sedan and minivan type vehicles that were subjected to speed changes ranging from about 20 to 50 kph (12 to 30 mph), with an average G level per speed change of about 9 to 15. The results indicate that children and infants seated behind a collapsing driver seat, even in low severity rear impacts of less than 25 kph, encounter a high risk of serious or fatal injury, whether or not rear intrusion takes place. Children seated in other rear seat positions away from significant front seat collapse, such as behind the stronger “belt-integrated” types of front seats or rearward but in between occupied collapsing front seat positions, are less likely to be as seriously injured.

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Effects of Front Seat Performance Failure on Rear Seat Occupant Injuries in Rear Impacts

10.1115/imece2000-2605 ◽

2000 ◽

Author(s):

Keith Friedman ◽

Tim Kenney ◽

Jack Bish ◽

Kemal Atesmen

Keyword(s):

Rear Seat ◽

Crash Severity ◽

Front Seat ◽

Occupant Injuries ◽

Serious Injury ◽

Rear Impacts ◽

A Performance

Abstract An analysis of rear end accidents involving rear seat occupants seated behind a front seat occupant was conducted examining the probability of serious injury as a function of both crash severity and front seat performance failure. Seat performance failure is when some element of the seat fails to do what it is designed to do, e.g. a seat back lock allows the seat back to move during the collision. The results suggest that the risk of serious injury is greater in the 6.7-11.2 m/s Delta-V crash severity range when the seat in front of the occupant suffers a performance failure.

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CHILDREN IN TRAFFIC ACCIDENTS

PEDIATRICS ◽

10.1542/peds.44.5.847 ◽

1969 ◽

Vol 44 (5) ◽

pp. 847-854

Author(s):

G. Anthony Ryan

Keyword(s):

Lower Limb ◽

Traffic Accidents ◽

The United States ◽

Rear Seat ◽

Age Group ◽

Front Seat ◽

Severe Injuries ◽

Rural Highways ◽

Points Of View ◽

Seating Position

The part that children play in traffic accidents has been studied by numerous workers from differing points of view. Slätis,1 in a study of 5,291 persons injured in traffic accidents and receiving medical treatment in Sweden, found that 16.3% were less than 15 years of age. An examination by Mackay2 of a series of 250 accidents investigated at the scene in Birmingham, England, found that children less than 16 years of age formed 6.2% of the 464 persons involved. In Brisbane, Australia, Jamieson and Tait3 found that children less than 15 years old formed 10.9% of a group of 1,000 admissions or deaths from traffic accidents. Gädeke4 in Germany, found children less than 15 years old were injured more often in rural accidents, that traffic accidents formed 35 to 40% of all fatal accidents in children, and that injuries to the head and lower limb were most common. In Sweden, Ekström, et al.5 found that the majority of children involved in accidents they studied were pedestrians or pedal cyclists, and 40% were between 5 and 9 years old. Moore and Lilienfeld6 reported on 31,001 occupants of known age in 14,520 automobiles involved in injury-producing accidents on rural highways in the United States. They found that children less than 12 years of age formed 9%, adolescents age 12 to 18 years formed 16%, and adults of more than 18 years formed 75%. They found that children received fewer and less severe injuries than adolescents or adults, in each seating position. Front seat passengers in each age group were injured more often and more severely than rear seat passengers.

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Biomechanical Study of Rear Child Chest Injury Measures Related to Collapsing Front Seats in Rear Impacts

Advances in Bioengineering ◽

10.1115/imece2003-43061 ◽

2003 ◽

Cited By ~ 1

Author(s):

Kenneth J. Saczalski ◽

Anthony Sances ◽

Srirangam Kumaresan ◽

Steve Meyer ◽

Joseph Lawson Burton ◽

...

Keyword(s):

Surrogate Data ◽

Rear Seat ◽

Biomechanical Study ◽

Test Method ◽

Chest Injury ◽

Motor Vehicles ◽

Set Up ◽

The Many ◽

Rear Impacts ◽

Rear Seating

Government recommendations have been made to place children into the rear seating areas of motor vehicles in order to alleviate airbag hazards in frontal impact. In most moderate to severe rear impacts, however, the adult occupied front seats will “yield” or “collapse” into the rear seat area and thus pose another potential head and chest injury hazard to the rear seated children. Numerous factors or variables, each with a wide parameter range, influence whether or not an occupied collapsing front seat will result in engagement with the rear occupant, and whether that engagement is likely to cause injury to the rear-seated occupant. A combined experimental and analytical method, employing instrumented surrogates in a sled-buck test set-up, has been utilized to study the multivariable potential injury problem of the rear-seated child in rear impact. A 3 year-old H-III surrogate, seated in the built-in booster seat of a minivan, was used as the rear seat passenger in this study. Five tests were utilized. The experimental surrogate data from the test method is combined into a “polynomial response function” that expresses “injury levels” (i.e. HIC and chest G) as a function of the many variables, and allows for analytical “interpolation and extrapolation” at variable combinations and ranges not tested. Actual accident cases were compared with the biomechanical injury measures. The present study presents a methodology to delineate the biomechanics of injuries using multivariate analysis.

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Warning signs to fasten seat belts result in higher rates of rear seat belt use in rideshare vehicles

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/1071181319631515 ◽

2019 ◽

Vol 63 (1) ◽

pp. 2046-2050

Author(s):

Kenneth Nemire

Keyword(s):

San Francisco ◽

Seat Belt ◽

Rear Seat ◽

Warning Signs ◽

Future Research ◽

Warning Sign ◽

Seat Belts ◽

Front Seat ◽

Passenger Vehicles ◽

Seat Belt Use

Using seat belts reduces traffic injuries and fatalities. Passengers in the rear seat typically use their seat belts less often than drivers or front-seat passengers. Seat belt use in the back is even less frequent in vehicles for hire such as taxi cabs and rideshare vehicles than in private passenger vehicles. This observational study of adult passengers video-recorded in rideshare vehicles in San Francisco found that a sign mounted at rear passenger seated eye level, and that warned of the risks of failing to wear a seat belt, resulted in significantly higher rates of seat belt use than for rear seat passengers not exposed to the warning sign. Results also showed that age, gender, and trip duration did not have a significant effect on rear seat belt use. Implications for future research and other countermeasures are discussed.

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