DETROIT – Although airbags have been around for more than 20 years, installation rates in North American vehicles will continue to grow, as auto makers strive to pack more safety systems into vehicle interiors.

Driving the movement will be an increase in government safety regulations, the growing interest in vehicle safety by consumers and the continued advancement of airbag technology, Theresa Marcantonio, North American component analyst for market forecasting firm CSM Worldwide, says here during a panel discussion at the Ward’s Auto Interiors Show.

Because driver and passenger frontal impact airbags have been mandatory in new vehicles for a number of years, most of the growth will come from the increased fitment of side, curtain and various alternative types of airbags.

Some 34% of ’05 model cars and 20% of ’05 light trucks built in North America were equipped with side impact airbags, Ward’s data shows. Those figures drop to 25% and 15%, respectively, for side curtain airbags.

By the end of the decade, nearly all new vehicles in North America will be equipped with side impact and side curtain airbags, Marcantonio predicts, with overall airbag installations increasing 63% by 2012.

This will be a daunting task for many auto makers, as vehicle interiors become increasingly complex and crammed full of additional entertainment and safety features.

Successfully integrating more airbags in new cars and trucks will be accomplished by the continued push to decrease the size of the systems, along with their fitment into alternative locations, says David Zecchin, airbag engineering director for Autoliv Inc.

Based in Stockholm, Autoliv is the world’s largest manufacturer of airbag systems with a 37% global market share, CSM says.

Exemplifying the shrinking of airbag systems over the years is one of the first systems Autoliv designed for General Motors Corp., Zecchin says. The steering-wheel-mounted unit weighed about 8 lbs. (3.6 kg), compared with one of the company’s modern units that weighs only 3 lbs. (1.4 kg).

The weight reduction not only allows airbags to fit into tighter spaces, but take on unique shapes, as well.

Autoliv supplies PSA Peugeot Citroen with the driver’s side front airbag for the new Citroen C4 small car. The compact, asymmetrical design of the unit was required to fit into the C4’s unconventional steering wheel, which features a central fixed hub that the steering wheel rim revolves around.

Zecchin also points to the industry’s first application of a door-mounted, side curtain airbag, which Autoliv supplies to Ford Motor Co.’s Volvo Car unit for use on the new C70 convertible.

In addition, Autoliv is testing frontal, downward-firing airbags mounted in the leading edge of a vehicle’s headliner, along with an inflatable carpet airbag module to protect a driver’s feet in a collision.

Placing compact, passenger-side airbags in existing openings in the dashboard, such as defroster vents, also is being studied, Zecchin says.

With these advancements in airbag installations come inherent hazards, such as properly educating emergency personnel on the various locations of an airbag unit’s sometimes volatile components.

“We want to know more about your business,” Mark Uttley, an emergency rescue-training consultant for the Windsor, Ont., Canada, Fire Dept. says of the cooperation between emergency personnel and auto makers.

The growing number of airbags in vehicles makes the work of emergency responders much more difficult, he says, because they usually have less than 20 minutes to extricate a trapped motorist and get them on their way to the hospital.

Airbags are inflated by pyrotechnic gas charges that are pressurized up to 7,000 psi (483 bar). These inflators become little bombs when they are heated or cut through with hydraulic emergency tools, Uttley says.

DaimlerChrysler AG’s Mercedes-Benz unit took a major step in addressing this problem when it released its new ’07 S-Class sedan earlier this year. The vehicle features cut lines etched into the front and rear window frames that indicate where it is safe to cut through the vehicle’s roof structure.

As vehicles continue to differentiate from each other and market segments fragment into ever-smaller niches, it will become harder for auto makers to incorporate a standard for airbag components and locations.

However, Uttley says greater education from auto makers and a standard method of marking all airbag component locations would be a big help.

msutton@wardsauto.com