NHTSA has documented that rollover accidents account for about 3-percent of all vehicle accident in the United States, yet are responsible for about 30- percent of the deaths, plus thousands of quadriplegics (tetraplegics). The principal mechanisms of injury causation are due to roof crush and occupant ejection.

Therefore, stronger roof design is needed to prevent the buckling and crushing down of the roof into the occupants’ “survival space”. And improved side window glazing, such as using laminated glass instead of tempered glass, will help prevent occupant ejection during rollovers, as well as in other impact modes.

Using rollover accident case examples and exemplar vehicles, detailed inspections and analysis show how and why the roof structures failed to adequately maintain the passenger compartment “survival space” and how the consequences often caused quadriplegic injuries. The history and technology of roof design shows safer alternative designs that would have made a safety difference.

It is clear that Federal Motor Vehicle Safety Standard 216 (FMVSS 216) on Roof Crush Resistance, which is a minimum requirement, has not ensured a reasonably safe roof in rollover accidents. Upgrades are need to ensure stronger roofs, with dynamic rollover testing to evaluate the total system of roof structural integrity, side window glazing, seatbelt restraints, side curtain airbags, and other measures that will help attain the Vision Zero compassionate goal of preventing needless deaths and injuries.