# Paul Akers Inc. — Hazardous Materials Safety Interpretation - **operation:** document - **citation:** 24-0086 - **title:** Paul Akers Inc. — Hazardous Materials Safety Interpretation - **source type:** guidance - **agency:** Pipeline and Hazardous Materials Safety Administration - **status:** guidance - **official:** true - **published on:** 2024-12-16 - **effective on:** Not available - **summary:** 24-0086 response to Paul Akers Inc. concerning 180.407. - **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-24-0086.json - **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-24-0086.md - **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-24-0086 - **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2025-01/240086.pdf **body:** <<>> U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 December 16, 2024 Mr. Alan Campbell Paul Akers Inc. 3155 West US 40 Greenfield, IN 46140 Reference No: 24-0086 Dear Mr. Campbell: This letter is in response to your September 17, 2024, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to transporting anhydrous ammonia or liquified petroleum gas in MC 330 and MC 331 cargo tanks. In your email, you ask whether these MC 330 and MC 331 cargo tanks qualify for a leakage test at 60 psi because they are used for transporting anhydrous ammonia or liquified petroleum gas depending on the time of the year. The answer is no. As referenced in §§ 180.407(h)(1)(ii) and (iv), both paragraphs state that MC 330 and MC 331 cargo tanks are required to be in dedicated service to either liquefied petroleum gas or anhydrous ammonia. Shipping both materials interchangeably throughout the year is not considered to be in dedicated service and—therefore—§§ 180.407(h)(1)(ii) and (iv) do not apply. I hope this information is helpful. If you have any more questions, please do not hesitate to contact this Office. Sincerely, Alexander Wolcott Acting Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division <<>> Vore From: INFOCNTR (PHMSA) To: Dodd, Alice (PHMSA) Cc: Hazmat Interps Subject: FW: interpretation Date: Friday, September 20, 2024 4:52:10 PM Attachments: image003.png 24-0086 Hello Alice, Please see the below interpretation request. Let us know if you need anything. Sincerely, Janaye From: alan@paulakers.com Sent: Tuesday, September 17, 2024 4:08 PM To: PHMSA HM InfoCenter Subject: interpretation CAUTION: This email originated from outside of the Department of Transportation (DOT). Do not click on links or open attachments unless you recognize the sender and know the content is safe. Hello, I am looking for some clarification on the leakage test pressure for a MC 330 and 331 vessel. The vessels are used solely for anhydrous ammonia or liquified petroleum gas depending on the season. Would this qualify them to be leakage tested at 60 psi? They are dedicated to haul just these two products. (h) Leakage test. The following requirements apply to cargo tanks requiring a leakage test: (1) Each cargo tank must be tested for leaks in accordance with paragraph (c) of this section. The leakage test must include testing product piping with all valves and accessories in place and operative, except that any venting devices set to discharge at less than the leakage test pressure must be removed or rendered inoperative during the test. All internal or external self-closing stop valves must be tested for leak tightness. Each cargo tank of a multi-cargo tank motor vehicle must be tested with adjacent cargo tanks empty and at atmospheric pressure. Test pressure must be maintained for at least 5 minutes. Cargo tanks in liquefied compressed gas service must be externally inspected for leaks during the leakage test. Suitable safeguards must be provided to protect personnel should a failure occur. Cargo tanks may be leakage tested with hazardous materials contained in the cargo tank during the test. Leakage test pressure must be no less than 80% of MAWP marked on the specification plate except as follows: (i) A cargo tank with an MAWP of 690 kPa (100 psig) or more may be leakage tested at its maximum normal operating pressure provided it is in dedicated service or services; or <<>> (ii) An MC 330 or MC 331 cargo tank in dedicated liquified petroleum gas service may be leakage tested at not less than 414 kPa (60 psig). (iii) An operator of a specification MC 330 or MC 331 cargo tank, and a nonspecification cargo tank authorized under § 173.315(k) of this subchapter, equipped with a meter may check leak tightness of the internal self-closing stop valve by conducting a meter creep test. (See appendix B to this part.) (iv) An MC 330 or MC 331 cargo tank in dedicated service for anhydrous ammonia may be leakage tested at not less than 414 kPa (60 psig). (v) A non-specification cargo tank required by § 173.8(d) of this subchapter to be leakage tested, must be leakage tested at not less than 16.6 kPa (2.4 psig), or as specified in paragraph (h)(2) of this section. - **truncated:** false - **body characters:** 4443