Bumper is used to protect the body of every car and trucks. The front-most or rear-most part, ostensibly designed to allow the car to sustain an impact without damage to the vehicle's frame or safety systems and save any other auto parts, but it has some limit that it will not withstand damage to high speed impacts. While bumpers were originally constructed of heavy steel and held clear from the bodywork, they have degenerated into light-weight structures of thermo-plastic or painted light metal — leaving them susceptible to damage from even light contact. US legislation
National Highway Traffic Safety Administration (NHTSA) issued the first US bumper standards, requiring to be capable of sustaining a 5 mile-per-hour (MPH) frontal crash and a 2.5 MPH rear crash without damage to safety systems. In 1974, the standard for rear crashes was raised to 5 MPH. Phase I of the standard was first applied to model vehicles. Phase II, beginning with 1980 models, the bumper itself could sustain only superficial damage in a 5 MPH crash. Initially, cars were mostly equipped with unsophisticated chunky protrusions of metal and plastic to achieve this standard in a cost-effective manner. Contemporary criticism considered them a stylistic detraction, and panned the additional weight of these bumpers on the already large 1970s American automobile.
At that time, NHTSA promised to conduct research and testing to provide consumers with accurate information on the quality of new car bumpers. Consumers Union filed a 1986 petition requesting the restoration of the Phase II standard and disclosure of bumper strength information. In 1990, NHTSA rejected that petition.
In later 1980s the design of bumpers evolved into largely hidden elements concealed by a single thermoplastic, painted fascia, again establishing itself as a stylistic rather than genuinely protective element. Protection dropped significantly and repair costs rose.
At the later 1990 NIHS study conducted four crash tests on three different model year examples of the then popular Plymouth Horizon, with the following damage results (1990 labor rates and parts prices):
* 1983 Horizon with No-Damage 5 MPH bumpers $ 287
* 1983 Horizon with weaker bumpers $ 918
* 1990 Horizon $ 1,476
In 2008, Canada announced it would harmonize its bumper standards with US standards, thereby allowing Canadians to more easily import US vehicles. The Canadian standard had required impact resistance up to 10km/hr or 6mph.
Legal issues
In many jurisdictions, bumper is legally required on all vehicles for safety reasons. The height and placement of bumpers may be legally specified as well, to ensure that when vehicles of different heights are in an accident that the smaller vehicle will not slide under the larger vehicle.
Smart Bumpers
Many cars now come with "smart bumpers" that can sense the distance to nearby cars during parking and warn of imminent collision.
visit our website : http://www.autobodypartsonline.com/bumpers.php
