Federal highway safety officials say a proposed requirement that all light trucks, vans and multipurpose vehicles be equipped with head restraints would prevent 6,300 injuries a year at a cost of less than $30 per vehicle.

Diane Steed, administrator of the National Highway Traffic Safety Administration, said Thursday in announcing the proposal that it had been prompted by the growing popularity of light trucks and vans.Head restraints have been required on passenger cars since 1969.

"Studies show head restraints are effective in reducing whiplash injuries to front-seat occupants in automobiles," Steed said.