Head injuries are a leading cause of death in side impacts, but until now, only the noggins of the wealthy got any extra protection.
Although not required by law, automakers such as BMW and Mercedes-Benz have been developing airbags designed specifically to protect people's heads in side-impact crashes and using safety as a selling point. While regular airbags come out of the steering wheel or dash, these special bags often come out of the roof or roof pillars.
But now some automakers producing less expensive vehicles are beginning to offer "head bags" for the masses, often as an option costing several hundred dollars.
Leading the charge
Ford Motor Co. is leading this safety charge with head-and-chest combination side airbags on vehicles ranging from its Windstar to the 2000 Taurus. It is a move that is likely to encourage competitors to offer them too. For example, Saturn officials recently said they hope to offer head bags in about a year on their L-Series models, which go on sale in July.
Consumers who are trying to decide whether it is worth spending the extra money for head protection instead of a fancier stereo should know that independent crash tests demonstrate that the bags apparently offer important protection in a side-impact crash.
Occupants are more vulnerable to injury in such a collision because there is only the metal of the door and a few inches of space separating them from an intruding object or vehicle. The side of a vehicle does not provide as much crash space as the front crush space that can absorb crash energy before it reaches the passenger compartment and injures people riding inside.
Occupants in small vehicles are also more vulnerable in a side collision with a larger vehicle such as a sport-utility vehicle or pickup truck because of the size mismatch.
When a car hits another car in the side, the doorsill — which is relatively strong — acts as a barrier to the intrusion. But an SUV or pickup truck rides higher and tends to hit in the middle of the door, at a particularly weak part of the car, resulting in more penetration into the occupant compartment.
The head airbags that are meant to protect occupants in such crashes come in many configurations. Some are sausage or curtain types that protect only the head. Some add head protection to side airbags that originally were designed to protect the chest. They may deploy from the roof or from the seat. Some protect just front-seat occupants; others protect rear occupants also.
A cubic liter of prevention?
Whatever the design, these airbags "can take a crash that would have caused a fatal head injury and turn it into one with almost a zero risk of a significant head injury," said Brian O'Neill, president of the Insurance Institute for Highway Safety.
The Insurance Institute has conducted several tests of such systems. Tests were conducted on two Lincoln Town Cars, a 1999 model with the head-protection system and a 1998 model without this technology. And in October 1997, the institute conducted crash tests on two BMW 5-Series models, one with the head protection and one without.
Ford's and BMW's airbags are designed differently, but both provided excellent protection. Ford's combination head-and-chest side airbags are housed in the side bolster of both front seats and deploy in two distinct sections to absorb energy near both the head and chest. BMW's inflatable tube "sausage" type is housed in the A-pillar and roofline and deploys diagonally across the front side window. They are separate from the side airbags.
In the most recent test, the Town Car was propelled sideways at 18 mph into a pole. Without the head-protection side airbag, the crash dummy's head hit the pole with more than enough force to cause death in an actual collision. The Head Injury Criterion score was 5,390, which means a force high enough to kill. It is more than five times the reference value of 1,000, which indicates the likelihood of a serious head injury, such as a skull fracture. When the same crash test was done with the side airbag that had head protection, the score was 376. In the BMW without the airbag to protect the head, the score was 4,720. With the head protection, it was 620.
"They are both good results," said O'Neill. "You're at the level where the risk of a significant head injury is essentially zero."
Although Ford isn't the first manufacturer to offer head airbags, it is the first to offer them in less expensive, more popular models. They are standard equipment on the Lincolns and optional on Ford and Mercury models. The price depends on the model, but it's in the $300 range.
The bags are being offered in the following models:
Ford, Lincoln and Mercury – 1999 Ford Windstar and Explorer, Lincoln Continental and Town Car, and Mercury Cougar and Mountaineer. 2000 Ford Focus and Taurus, Lincoln LS and Mercury Sable.
Head airbags are also being offered as standard equipment by these manufacturers:
Jaguar: The 2000 S-Type; all 1998, 1999 and 2000-model sedans (the XJ8 models — XJ8, XJR supercharged, XJ8 long-wheelbase and the Vanden Plas).
BMW: The all-new 1999 and 2000 323i and 328i sedans; 2000-model 323Ci and 328Ci coupes; 1998, 1999 and 2000 5- and 7-series models.
Mercedes-Benz: The 1999 E-Class sedan; 2000 E-Class sedan and wagon; 2000 S-Class; the 2000 CL coupe.
Saab: All 9-3 models since May 1998 and all 9-5 models since October 1998.
Volvo: The 1999 and 2000 S- and V-70 models; the 1999 and 2000 S80 luxury sedan; 2000-model S- and V-40 models.