National Tank Truck Carriers, Inc. — Hazardous Materials Safety Interpretation

Page 1f Transportatio S.Departmen 400 Seventh Street, S.W. Washington, D.C. 20590 JAN - 8 2001 Mr. John L. Conley Ref. No. 00-0336 Vice President National Tank Truck Carriers, Inc. 2200 Mill Road Alexandria, Virginia 22314 Dear Mr. Conley: This responds to your letter, dated November 29, 2000, concerning cargo tank inspections and tests required by the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask if an insulated MC 330 or MC 331 cargo tank must be pressure tested in accordance with § 180.407(d). The answer is yes. Section 180.407(c) establishes periodic inspection and test requirements for specification cargo tanks. Generally, an MC 330 or MC 331 specification cargo tank must undergo a visual external inspection each year. Section 180.407(d) requires a visual internal inspection in place of the visual external inspection for insulated cargo tanks, except for MC 330 and MC 331 cargo tanks. However, for cargo tanks, including MC 330 and MC 331 cargo tanks, tor which an internal visual inspection is precluded, either because the tank has an internal lining or coating or is not equipped with a manhole, § 180.407(d) requires the tank to be pressure tested in accordance with § 180.407(c) and (g). Consistent with § 180.407(d), the chart in § 180.407(c) indicates that, except for MC 338 cargo tanks, all cargo tanks that are insulated with no manhole or are insulated and lined must be pressure tested annually. You are correct that, even where insulation precludes a visual external inspection of the tank shell, a visual external inspection of a cargo tank's piping, valves, gaskets, manholes, emergency conducted in accordance with § 180.407(d)(2). The cargo tank must be marked as specified in devices, remote closures, and all major appurtenances and structural attachments must be $ 180.415 to indicate successful completion of the visual external inspection. 180.407 000336#

Page 2I hope this information is helpful. If you have further questions, please do not hesitate to contact this office. Sincerely, The Thomas G. Allan Senior Transportation Regulations Specialist Office of Hazardous Materials Standards#

Page 3Gorsky $180.407 (d) NATIONAL TANK Cargo TaNks NTTC NATIONAL TANK TRUCK CARRIERS, INC. TRUCK CARRIERS THE NATIONAL ORGANI FOR HIRE TANK 18450-0336 INDUSTRY CLIFFORD J. HARVISON PRESIDENT 2200 MILL ROAD • ALEXANDRIA, VA 22314-4677 PHONE: 703/838-1960 • FAX: 703/684-5753 November 29, 2000 Mr. Edward Mazzullo Office of Hazardous Materials Standards Research and Special Programs Administration U.S. Department of Transportation Washington D.C. 20590 Dear Mr. Mazzullo: We would appreciate an interpretation of the Hazardous Materials Regulations in Part 180.407 (d) which reads as follows: (d) External visual inspection and testing. (1) Where insulation precludes external visual inspection, the cargo tank, other than an MC330 or MC331 cargo tank, must be given a visual internal inspection in accordance with section 180.407(e). The tank must be hydrostatically or pneumatically tested in accordance with section 180.407 ( c) and (g) Does an insulated MC330 or MC331 cargo tank have to be hydrostatically or pneumatically tested? It is clear that there is no requirement for an internal to all tanks or tanks except MC330/331 tanks. We have received different inspection, but "The tank" in the second sentence is not clear whether it applies interpretations from the field, so would appreciate your guidance. We do believe that other parts of the external visual inspection must be conducted and the tank marked with a "V" Thank you for your assistance. Sincerely, pola Coule ohn L. Conley Vice President#