Proposed rule

Feb. 1, 2011
PHMSA moving forward with effort to ban wetlines

DESPITE lingering doubts regarding the extent of the safety risk posed to motorists, the Pipeline and Hazardous Materials Safety Administration (PHMSA) is moving ahead with efforts to ban wetlines on most tank trailers. PHMSA's notice of proposed rulemaking on the issue was published January 27.

PHMSA seems in a big hurry to wrap up this rulemaking effort. The tank truck industry has been accorded a relatively short 60-day comment period. Comments on HM-213D are due no later than March 28.

The proposed rule would cover tank trailers used to transport Class 3 flammable liquids. In addition to gasoline, Class 3 products include acetone, alcoholic beverages, amines, benzene, butyl nitrates, isocyanates, methanol, paints and coatings, pesticides, and vinyl acetate.

Like the failed legislation proposed in the last Congress, the proposed rule does not address all trailer configurations used by tank truck fleets. The rule does not address Michigan-style trailers or truck-and-trailer combinations that are widely used in the west.

However, most tank trucks would be exempt, but PHMSA leaves the door open to add these vehicles in the future. The rule also would not cover cargo tank motor vehicles transporting flammable products that have been reclassified as combustible.

The regulation would apply to any new trailers (DOT406 and DOT407 units in many cases) built two years after the effective date of the final rule. These trailers would need a means of allowing no more than 0.26 gallons of product in each loading line or be constructed with accident protection similar to rear bumper requirements.

There is no grandfather clause for the existing tank trailer fleet. Trailers in service at the time of the final rule would have to be brought into compliance with the requirements no later than 12 years after the effective date of the final rule. National Tank Truck Carriers continues to express concerns about the safety risk posed to cargo tank mechanics by the retrofit requirement.

In justifying the proposed rule, PHMSA officials totally discounted economic and safety concerns of the tank truck industry. Throughout the many years that the issue has been discussed, the industry has argued consistently and validly that wetlines purging systems would do little or nothing to improve safety.

The federal government's own statistics indicate that the risk of a fatal wetlines incident is approximately one in 30 million. In fact, the odds of someone being struck by lightning during his lifetime is 6,000 times greater than the odds of being killed in a wetlines incident.

PHMSA states that the cost of installing a wetlines purging system should be around $2,585, which might be optimistic since no production-volume purging system is available at this time. Some industry estimates suggest that the real cost will be at least $5,000 per trailer. The agency also contends that no extra costs would be incurred during retrofits because they could be done at the same time as periodic pressure tests.

The tank truck industry had argued during previous rulemakings that it would be safer and faster if product lines were purged at the loading rack. PHMSA totally rejected that idea, and the proposed rule calls for the piping to be purged after the tractor-trailer rig pulls away from the loading rack.

PHMSA makes the assumption in the proposed rule that sight glasses would be specified with the external piping on tank trailers covered by the rule. This would make it easy for drivers and enforcement officials to verify that the purging system is working properly, according to PHMSA officials.

After failing in past regulatory attempts to cost-justify a wetlines-purging requirement, the PHMSA bureaucrats came up with something called “sensitivity analysis” to justify the latest proposal. This theory seems to suggest that as gasoline prices rise, more people will be riding in each car on the highway, which means more casualties every time a car runs into a tanker vehicle.

Written comments on HM-213D can be submitted through the Federal eRulemaking portal ( or they can be faxed to 202-493-2251. Mail submissions should be sent to Docket Operations, US Department of Transportation, West Building, Ground Floor, Room W12-140, Routing Symbol M-30, 1200 New Jersey Ave, SE, Washington DC 20590.