Cars made between 1980 and 1982 had even stricter standards, which mandated that the bumpers survive “5 MPH longitudinal front and rear barrier and pendulum impacts, as well as no damage to the bumper itself beyond a 3/8 inch 'dent' and 3/4 inch 'set' or displacement from original position.”
Enter the less-government-is-a-good-thing Reagan Administration, which loosened the regulations for the 1983 model year (one wonders whether they were lobbied by manufacturers, or whether then then-directors of NTHSA found the requirements too onerous). The 1983 regulations, which have survived relatively unchanged to the present day, reduced the impact speed from 5 to 2.5 mph, and corner pendulum impact speeds from 3 to 1.5 mph. In addition, the requirement to prevent damage to the bumper itself was dropped.
It's now the 1983 bumper regulations' silver anniversary, and before we light the candles on the cake, the Insurance Institute for Highway Safety would like to have a word with us, the car buyers of America. They recently did some crash testing of 2008 model-year vehicles, and the results may make you reach for your stash of party noisemakers to sound an alarm.
Low-speed crashes of 3 to 6 mph in late-model vehicles can trigger very expensive repair bills. Because the need to protect the bumper itself was excised from the rulebook 25 years ago, grilles, hoods, fenders and other structures can be damaged from what should be minor bumper-thumper incidents.
In tests of luxury cars, the IIHS showed that a Mercedes-Benz C Class sustained $5,486 worth of damage when run into a barrier at 6 mph. Granted, that is over the legal limit, but remember that 6 mph is walking speed—as Ralph Vartabedian of the L.A. Times quipped, “If the human body were built like a car, you couldn't walk into a wall without ending up in intensive care.”
Other cars fared equally dismally in the pocketbook department: An Infinity G35 cost $5,223 to repair, while a Volkswagen Passat cost $4,594 to fix. Some cars' repair bills were quite a bit less, however—the Lincoln MKZ only cost $669 to fix after a corner impact, while the best-performing frontal-impact car tested was the Mitsubishi Galant, with $929 in damage.
The winner in the insurance institute's tests, however, was a car that's no longer made: a 1981 Ford Escort (how did they manage to have that car lying around waiting to be tested, we wonder?). Because this car was from the days of the really stringent bumper rules, it sailed through the corner test with zero damage, and only sustained $86 worth of damage to the front bumper (which was cosmetic damage to the bumper itself). The rear bumper sustained $383 in damage, but remember that the test was for 6 mph, one mile per hour greater than the standard it should have met.
One reason that cars sustain so much damage today is that the styling integrates the bumper into the front end of the car in such a way that it's often hard to determine where the front (or back) end of the car ends and the bumper begins. And there's no requirement for a lateral steel crossbeam, so manufacturers put foam in its place. It may absorb some energy, but not enough to protect the bumper, let alone surrounding structures. And with some vehicles built to such precise tolerances, any damage may render some vehicles practically unrepairable. Consider recent BMW 5- and 6-series vehicles with aluminum frames engineered so precisely that if the frame is distorted more than 1 millimeter, the frame itself must be replaced. (Or the vehicle could be totaled.)
Would we want our vehicles to look like some of the ungainly designs of the 1970s, with protruding hunks of metal protecting our cars from low-speed impacts? If enough people complain about $5000 repair bills for a bump in the parking lot, we may be able to force a change in the regulations. Here's hoping engineering has progressed beyond the 1970s so that we can have structurally safe bumpers that look like they're integrated into the car's design, as opposed to the we'll-design-the-car-and-then-stick-the-bumper-on-it philosophy of years ago.