{"operation":"document","citation":"98-0251","title":"National Tank Truck Carriers, Inc — Hazardous Materials Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"1998-10-08","effective_on":null,"summary":"98-0251 response to National Tank Truck Carriers, Inc concerning 180.405, 180.407.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-98-0251.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-98-0251.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-98-0251","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/1998/980251.pdf","body":"<<<PAGE 1>>>\n\nof Transportation\nU.S.Department\n40s segion, .. 2550\n2059\nSpecial Programs\nResearch and\n. ост & 1998\nAdministration\nMr. Clifford J. Harvison\n•\nPresident\nRef. No. 98-0251\nNational Tank Truck Carriers, Inc.\n2200 Mill Road\nAlexandria, VA 22314-4677\nDear Mr. Harvison:\nThis 1s in response to your letter dated August 25, 1998,\n•\nrequesting clarification of repair and replacement requirements\nvehicles under the Hazardous Materials Regulations\nfor reclosing pressure relief valves on MC 306 cargo tank motor\nParts 171-180). Your questions are answered as follows:\n(HMR; 49 CFR\nQ1.\nrelief valve from a MC 306 cargo tank motor vehicle. The valve\nAfter August 31, 1998, we removed a reclosing pressure\nfails a \"bench test\" due to a faulty mechanical element within\nthe valve.\nThe mechanical element is repaired and the valve\nsuccessfully passes the \"bench test\". May this valve be returned\nto service on an MC 306 cargo tank motor vehicle?\nA1.\nYes. The HMR permits the return of a refurbished (repaired)\nreclosing pressure relief valve to the cargo tank from which it\nwas removed.\nHowever; if the repaired pressure relief valve no\nlonger meets the performance requirements of the original\nspecification (MC 306), the valve must be replaced.\nreplacement valve must\nmeet the DOT 400-series pressure surge\nrequirements under § 180.405 (h) (2).\nrelief valve from a\n22. After August 31, 1998, we removed a reclosing pressure\nfails\na \"bench test\" and the cause is determined to be the\n• MC 306 cargo tank motor vehicle.\nThe valve\nfailure of a gasket, external to the valve assembly. We replace\nthe gasket, and the\nvalve successfully passes the\n\"bench test\".\nMay this valve be returned to service on an MC 306 cargo tank\nmotor vehicle?\nA2. Yes. :\nRegardless of whether the repair or refurbishment is\ninternal or external to the valve assembly (for example,\nreplacement of the valve seats, springs or gaskets), if the\npressure relief valve meets the original specification\nperformance criteria discussed in Al above, it may be returned to\nservice on the cargo tank motor vehicle from which it was\nremoved.\n180.407\n\n<<<PAGE 2>>>\n\nI hope this satisfies your inquiry. If you need additional\nassistance, please do not hesitate to contact us.\n• Sincerely,\nR. Ryan tat\nfoR Hattle I. Mitchell, Chief\nRegulatory Review and Reinventior\nOffice of Hazardous Material Standards\n\n<<<PAGE 3>>>\n\n-NATIONAL TANK\nNTTC\nNATIONAL TANK TRUCK CARRIERS, INC.\nTRUCK CARRIERS\nTHE NATIONAL\nORGANIZATION SERVING THE FOR•HIRE\nTANK\nTRUCK\nINDUSTRY\nCLIFFORD J HARVISON\nPRESIDENT\n2200 MILL ROAD • ALEXANDRIA, VA 22314-4677\nPHONE: 703/838-1960 • FAX: 703/684-5753\nAugust 25, 1998\nMr. Alan I. Roberts\nAssoc. Admin. for Hazardous Materials Safety\nU.S. Department of Transportation\nResearch & Special Programs Administration\nWashington, DC 20590\n(Via Fax -- Hard Copy To Follow)\nDear Mir. Roberts:\nPlease consider this letter a request for an interpretation of the Administrator's Hazardous Materials\nRegulations.\nNational Tank Truck Carriers, Inc. (NTTC) is the international trade association of the tank truck industry\nwith over 200 corporate members which specialize in the transportation of hazardous materials in cargo\ntank motor vehicles.\nreading of this regulatory language indicates to some that if a reclosing pressure relief valve fails to meet\nOur concerns center on an apparent ambiguity at 49 CFR 180.407(g)(ii)(A) and (B). A strict \"literal\"\nthe provisions of \"(A)\" (during the so-called \"bench test') that pressure relief valve cannot be repaired\nand returned to service. It must be replaced. After August 31, 1998, it must be replaced with a reclosing\npressure relief valve that complies with the equivalent \"DOT 400\" series cargo tank specification.\nBelow, I have outlined two scenarios, followed by a question.\nSCENARIO \"A\" -- After August 31, 1998, a reclosing pressure relief valve is removed from an MC 306\nof the valve. The mechanical element is repaired and the valve \"passes\" a subsequent \"bench test\". May\ncargo tank. It fails the \"bench test\", and it is determined that the failure is caused by a mechanical element\nthis valve be returned to service of a cargo tank motor vehicle?\nHittie\n\n<<<PAGE 4>>>\n\n*.\nSCENARIO \"B\" - After August 31, 1998, a reclosing pressure relief valve is removed from an MC 306\nthe valve assembly. The inspector/testor replaces the gasket, and the valve \"passes\" the \"bench test\".\ncargo tank. It fails the \"bench test\", and it is determined that the failure is caused by a gasket, external to\nMay this valve be returned to service on a cargo tank motor vehicle?\nMr. Roberts, given the pendancy of the August 31, 1998 \"trigger date\", a prompt response would be\nappreciated. Thank you for your consideration in this matter.\ntruly yours,\nPresident\n- --","truncated":false,"body_characters":4765}