DETROIT – Head-restraint suppliers will leave auto makers to their own devices when contemplating solutions to a new U.S. federal regulation scheduled to take effect in 2009.

Unlike stability-control suppliers that rankled OEMs by promoting their systems directly to consumers at the height of the rollover debate, head-restraint vendors have no plans to champion the use of pricey active systems – a move that could dramatically improve occupant safety and comfort, while also boosting suppliers’ profit margins.

“Active systems are easier to market because it’s something that the consumer can recognize,” admits Adam Wittman, lead safety engineer at Intier Automotive Seating.

“But that doesn’t mean it will provide them with an increased safety benefit over a passive system,” he says here at the Ward’s Auto Interiors Show.

Both are allowed under FMVSS 202a, which is intended to prevent or lessen the severity of neck injuries by narrowing the gap between a restraint and an occupant’s head.

Using a pyrotechnic charge or some mechanical means triggered by a crash event, active systems automatically reposition restraints for optimal performance. But some early versions were ineffective because they were paired with seat designs that failed to account for the restraint’s deployment.

Passive systems, which are cheaper, feature static head restraints. And coupled with the proper seat design, they can be made to comply with FMVSS 202a for a fraction of an active system’s cost, though suppliers are mum on actual numbers.

However, comfort is sometimes compromised, because static restraints are fixed in the optimal position, close to the occupant’s head.

As Washington and public safety advocates shone a spotlight on SUV rollovers in 2002, Continental Automotive Systems North America and Robert Bosch Corp. established the Electronic Stability Control Coalition and marketed stability control directly to the public.

Auto makers felt the pressure to adopt the technology, and for model-year ’06, installation rates on domestically built cars was 14.4%, nearly double the rate for model-year ’04, according to Ward’s data.

Heightened awareness of ESC’s benefits compelled Detroit’s Big Three auto makers to make the technology standard equipment on most of their SUVs. The National Highway Traffic Safety Admin. is pursuing a mandate to require ESC on all vehicles by 2011.

Gerald Locke, safety engineering director for Lear Corp.’s seating systems division, does not anticipate the formation of a supplier-led lobby for active restraint systems. The industry is content to let the Insurance Institute for Highway Safety be their voice, he says.

The IIHS publishes regular reports on the effectiveness of various head-restraint systems.

“They’re doing a pretty good job for us,” Locke says.

As for the proliferation of active-restraint systems, he adds: “It sounds like it should be a slam-dunk, but it’s just not that simple.”

Cost is the primary obstacle, which is why active systems are mostly the domain of luxury and premium brands such as Mercedes-Benz, Volvo and Saab.

However, Dimitri Moustakeas, Grammer’s vice president-sales and engineering for the North American automotive market, sees an encouraging trend on the horizon.

“As you see multiple generations being developed, you’ll see the cost go down,” Moustakeas says. That’s what is happening in Europe, where Grammer is a major player.

Lear will debut a second-generation system in North America this fall, Locke says. But he declines to reveal the nameplate.

Whereas current systems are triggered by pressure from an occupant’s shoulders as they sink into a seat on impact, Lear’s second-generation system is more sensitive, responding to pressure from the occupant’s lumbar and pelvic regions.