U.S. Transportation Secretary Ray LaHood announced tough, new roof standards that will significantly strengthen vehicle roof structures and improve rollover crash protection.

"Rollovers are the deadliest crashes on our highways and today's rule will help occupants survive these horrific events," said Transportation Secretary Ray LaHood.

The new regulation from the National Highway Traffic Safety Administration will double the current roof strength requirement for light vehicles weighing up to 6,000 pounds. It specifies that both the driver and passenger sides of the roof must be capable of withstanding a force equal to three times the weight of the vehicle.

The current standard calls for roofs to withstand 1.5 times the weight of the vehicle, applied to one side of the roof, for light vehicles up to 6,000 pounds.

Heavier vehicles from 6,000 to 10,000 pounds, which have never been regulated, must now have both sides of the roof capable of withstanding a force equal to 1.5 times the weight of the vehicle.

The phase-in schedule, which begins in September 2012, will be completed for all affected vehicles by the 2017 model year.

Secretary LaHood also reminded Americans that wearing a safety belt will significantly improve the chance of survival in a rollover crash. They keep people in their seats and can prevent them from being ejected in rollover crashes.

"These new standards go a long way toward reducing deaths, but safety belts are the first, most important step everyone should take to protecting themselves and their families," he said.

The tougher roof crush requirements are part of a comprehensive plan to address rollover crashes, which kill about 10,000 people annually. That approach includes a mandated electronic stability control system, which helps prevent the rollover from occurring.