Physics.edu
Head Restraints
Written by N.N
Head restraints prevent whiplash injury in the passengers’ necks, specifically when experiencing a rear-impact crash.
Head restraints were installed largely in response to the Federal Motor Vehicle Safety Standard 202. The General Services Administration established a requirement for all passengers cars in 1966 and the National Highway Traffic Safety Administration established a requirement for all passenger cars in the US to have head restraints in 1968. From there, head restraints have been part of the Federal Motor Vehicle Safety Standard 202.
Whiplash is one of the most common injuries in motor vehicle crashes and is a predominant injury in cases of rear impact crashes. Whiplas occurs when the passenger's head jerks forward due to the inertia, past the seatback, and snapping/injurring the passenger's neck. This is a serious issue as it results in many deaths or even life long conditions.
A head restraint stops the passenegr's head from moving forward and backward in the first place, preventing whiplash. The head restraint is an etension of the seatback and supports the head and neck, ultimately preventing hyper-extension.
There are two types of head restraints, adjustable and integral. Adjustable head restraints are as they say, able to adjust to the passenger's requirement. Integral, however, are set and cannot change position. Results shown by the (National Crash Severity Study also known as the NCSS) show that integral seats are significantly more effective than adjustable restraints as the adjustable restraints can be adjusted incorrectly, therefore causing more harm than protection. Integral headrests are more effective as they were appropriately attached, unlike adjustable head restraints.
There are many advantages with head restraints but these also come with disadvantages. Further improvements are continually being made to reduce the disadvantages that come with head restraints and increase the advantages.
