Roof Crush Test

Rollover test and nass case analysis nhtsa june 1992.

Roof crush test.

The relationship between injury levels and intrusion or roof crush has. In the test the strength of the roof is determined by pushing an angled metal plate down on one side of the roof at a slow but constant speed and measuring the force required to crush the roof. The number of occupant injuries is significantly higher. Supplemental notice of proposed rulemaking snprm.

Although their procedure is similar to that of fmvss 216 216a the requirement to earn the highest rating is 4 0 times the vehicle s curb weight. 49 cfr parts 571 and 585216 as part of a comprehensive plan for reducing the risk of rollover crashes and the risk of death and serious injury in those crashes this final rule upgrades the agency s safety standard on roof crush resistance in several ways. Researchers applied force to the roofs until crush reached 10 inches measuring the peak force required for 2 inches of crush 5 inches of crush and 10 inches. Roof crush resistance 222 13 kb final rule.

If the vehicle being tested is a multipurpose passenger vehicle truck or bus that has a raised roof or altered roof and the initial contact point of the static loading device is on the raised roof or altered roof to the rear of the roof over the front seat area the plate is positioned so that the midpoint of the rearward edge of the lower surface of the static loading device is within 10 mm of the transverse vertical plane located at the rear of the roof over the front seat area. Roof crush is the failure and displacement of an automobile roof into the passenger compartment during a rollover accident. The force applied relative to the vehicle s weight is known as the strength to weight ratio. A test program like the very successful series produced by the iihs for offset frontal impacts would be more effective in the short run at least for improving roof strength.

Earlier in february 2009 the iihs announced a new rating system based around roof crush testing. Federal motor vehicle safety standards. The recently released nhtsa study roof crush analysis using 1997 2001 nass case review which has been in the works for nearly four years reviewed nass rollover crashes in an effort to determine whether roof deformation patterns identified in an earlier agency study were still valid for current vehicle designs see upgraded rollover roof crush protection. Every year approximately 10 000 americans are killed in rollover accidents accounting for about 30 of all light vehicle occupant fatalities.