The Federal Research and Special Programs Administration (RSPA) issued a joint notice of proposed rulemaking (NPRM) with the Federal Motor Carrier Safety Administration (FMCSA) that would amend 49 CFR Part 173 to add flammable liquids to a prohibition against transporting hazardous materials in unprotected product piping on existing and newly manufactured Department of Transportation specification cargo tank motor vehicles.
According to the NPRM, hazardous materials regulations prohibit the retention of certain liquid hazardous materials in the external product piping or wet lines of a DOT specification cargo tank unless the cargo tank motor vehicle is equipped with bottom-damage protection devices. The prohibition applies to Divisions 5.1 (oxidizer), 5.2 (organic peroxide), 6.1 (toxic) and Class 8 (corrosive to skin only). The current rule does not apply to flammable liquids.
Wet lines located underneath the cargo tank on DOT specification cargo tank motor vehicles typically remain filled with product after loading and unloading. RSPA points out that a five-compartment tanker carrying gasoline, which is not covered in the current regulation, can retain 30 to 50 gallons of product in the external piping, posing a hazard if a passenger vehicle strikes the side of the tanker.
On February 10, 2003, RSPA published an advance notice of proposed rulemaking (ANPRM 68 FR 6689) to solicit comments and information regarding methods to reduce the safety risks associated with retention of lading in unprotected wet lines. Based on comments received, RSPA and FMCSA are proposing a prohibition against carriage of flammable liquids in wet lines unless the vehicle has bottom damage protection. For vehicles transporting gasoline, the proposed rule would limit to one liter or less the amount of gasoline that could remain in each pipe after it is drained.
The rule does not propose any specific method to achieve compliance. RSPA says the performance standard permits industry-wide latitude to develop measures to meet the requirement.
The notice of proposed rulemaking (Docket No. RSPA 99-6223 HM-213B) is located on the Department of Transportation Web site at http://hazmat.dot.com. The deadline for comments is February 28, 2005.