Common language

Feb. 1, 2007
THE IRISH playwright and English immigrant, George Bernard Shaw, said the United States and the United Kingdom are two countries divided by a common language.

THE IRISH playwright and English immigrant, George Bernard Shaw, said the United States and the United Kingdom are “two countries divided by a common language.” A similar circumstance appears to apply when discussing the Canadian and United States regulations for trailer rear underride guards.

Peter Weis of Polar Corp discussed the differences between the United States regulations and those in Canada at the National Tank Truck Carriers 2006 Cargo Tank Maintenance Seminar October 16-18 in Nashville, Tennessee.

While the United States established the underride guard rules in 1998, Canada now has more stringent rules that take effect September 1, 2007. “The difference may have a wide-reaching effect,” Weis said, predicting that many US-certified tank trailers will need Canadian-compliant rear impact guards.

Canadian rules will require higher testing loads and energy absorption than US regulations. In addition, the Canadian rules call for a 22-inch ground clearance dimension after testing, while the US rule requires a 22-inch maximum clearance only.

Weis said that dual certification to both regulations is possible because the US rule does not have an upper loading limit. However, it would be necessary to perform the US “P3” (P3=22,480 pounds) test in addition to the Canadian tests. ”A Canada rigging will, in some cases, require stronger frame rails and support brackets, and will likely add significant weight,” he added. “Early estimates were 150-200 pounds.”

Turning to maintenance of the equipment, Weis said carriers should be sure mechanics understand the design being repaired. For example, a manufacturer may be using special high-tensile materials. In addition, slots and holes may be necessary for energy absorption. He pointed out that 49 CFR 393.86 prohibits changing the dimensions of the FMVSS bumper during repairs and that certification labels must be kept legible.

All of these differences spring from a 1997 Canadian study by Transport Canada that the agency considers to be supplemental to tests conducted in the United States by the National Highway Traffic Safety Administration (NHTSA) in 1992-1993.

Transport Canada determined that small cars have the ability to protect occupants in impacts up to 56 kilometers per hour (34 miles per hour); US rigging is effective in preventing underrides up to 48 kph/29 mph; and Canadian rigging is effective at 56 kph/34 mph.

As a result, Canada's officials determined that because Canada has a higher concentration of small cars, there is more to gain by protecting that segment of the population.

Finally, units with Canadian rigs can't travel to the United States because they would need to be certified to NHTSA regulations unless they meet dual-certified guard requirements or wheels set back 12 inches from tire to rear of trailer. Trailers certified to US safety regulations are required to comply with the US rigging regulations, with the same two exceptions above.

Units with the US rigging that are built after September 1, 2007, can't be sold or domiciled in Canada. “Perhaps we'll see import restrictions on vehicles being moved to Canada similar to the acceptable manufacturer's list currently being used to verify brake compliance,” Weis said.