WASHINGTON — The National Highway Traffic Safety Administration (NHTSA) has cleared up an ambiguous safety-related situation regarding trailer tires that's been an issue for the past 18 years.
NHTSA recently clarified its position on which federal safety regulations should apply to certain types of tires intended for use on trailers.
In a statement posted in the Federal Register on Aug. 31, NHTSA states that certain types of tires intended for use on trailers (specialty trailer, or "ST") and/or farm implements, as well as tires with a rim diameter of 12 inches or less, are subject to safety-related terminology in Federal Motor Vehicle Safety Standard (FMVSS) 119, which applies to tires used on vehicles with a gross vehicle weight of 10,000 pounds or more.
The situation first arose in 2003 when NHTSA was promulgating a new safety standard — FMVSS 139 — in the wake of the Firestone Wilderness and ATX SUV tire recall snafu.
For the past eight years, language in a 2013 NHTSA memorandum had said tires subject to terms in two separate standards, FMVSS 109 — which dates from 1967 — and FMVSS 119 — which went into effect in 1973.
Because of the unintended ambiguity, makers of said tires were in a state of limbo, not certain which standards applied to their products.
In 2013, the Tire & Rim Association — with support from the Rubber Manufacturers Association (now the U.S. Tire Manufacturers Association) and the European Tyre & Rim Manufacturers Association — petitioned NHTSA for a clarification of these rules.
After reviewing the matter and considering the various submissions, NHTSA now acknowledges that FMVSS No. 109 does not specify test conditions for specialty tires with maximum inflation pressures, and that without this provision, it cannot test specialty tires for compliance with FMVSS No. 109.
To remedy the situation, NHTSA has made the designated specialty tires subject to FMVSS No. 119, which specifies test conditions based on load range designations. Doing so provides the tire industry flexibility to change maximum tire inflation pressures for specialty tires without first requesting regulatory changes from NHTSA.