History of U.S. Rulemaking

1967 The National Highway Traffic Safety Administration (NHTSA) of the U.S. Department of Transportation (DOT)issues an Advance Notice of Proposed Rulemaking.

1969 NHTSA issues Notice of Proposed Rulemaking for a rear underride device 18 inches from the ground. Proposed regulation covers most trucks and trailers more than 10,000 lbs. Gross vehicle weight rating(>10K GVWR); agency claims proposal could save up to 100 lives per year; static testing for 75,000 lbs. Centric load capability; no specific design indicated.

1970 NHTSA issues second(revised) Notice of Proposed Rulemaking; guard still would be 18 inches from ground; covers most trucks and trailers >10K GVWR; static test slightly revised and centric load capability lowered to 50,000 lbs.; no specific design indicated.

1971 NHTSA terminates rulemaking.

1977 NHTSA reopens rulemaking with new Advance Notice of Proposed Rulemaking; indicates that tests show that 18-inch-high guard that is energy-absorbing is preferable.

1981 NHTSA issues Proposed Notice of Rulemaking for a device 22 inches from the ground; still acknowledges that energy- absorbing guard is preferable; covers most trucks and trailers >10K GVWR; claims that up to 60 lives per year could be saved; static test revised; centric and extreme offset loads of 11,240 lbs., offset load of22,480 lbs. near horizontal beam/ vertical strut intersection; design specified.

1992 NHTSA issues Supplemental Notice of Proposed Rulemaking for a device maximum 22 inches from ground; again acknowledges superiority of energy-absorbing guard; admits that NHTSA design is only a modification of Interstate Commerce Commission’s guard from early 1950’s; proposed rule now an equipment-standard rather than vehicle-standard; test fixture no longer specified; same centric and offset load capabilities as 1981 proposal.

Proposed rule covers half or less of trailers/ semi-trailers — all single-unit now exempted; claims that 9 to 19 lives could be saved each year; 776 to 114 non-minor injuries could be prevented; 18 to 27 percent Passenger Car Intrusion underride crashes prevented.