# HMT Associates, L.L.C. — Hazardous Materials Safety Interpretation - **operation:** document - **citation:** 99-0224 - **title:** HMT Associates, L.L.C. — Hazardous Materials Safety Interpretation - **source type:** guidance - **agency:** Pipeline and Hazardous Materials Safety Administration - **status:** guidance - **official:** true - **published on:** 2000-01-31 - **effective on:** Not available - **summary:** 99-0224 response to HMT Associates, L.L.C. concerning 173.6. - **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-99-0224.json - **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-99-0224.md - **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-99-0224 - **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/1999/990224.pdf **body:** <<>> of Transportation US. Department 400 Seventh Street. S.W Special Programs Research and Washington, D.C. 20590 JAN 3 1 2000 Administration Mr. E.A. Altemos HMT Associates, L.L.C. Ref. No. 99-0224 1850 K Street, N.W. Suite 200 Washington, DC 20006-3500 Dear Mr. Altemos: This is in response to your letter of August 18, 1999, concerning applicability of the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180) to a compressed air system which is liquid from a bulk tank on the vehicle. permanently mounted on a commercial motor vehicle and used to discharge a non-hazardous You ask whether such a system is considered to be outside the scope of the HMR, consistent with an opinion issued by this office on July 26, 1994, in the same manner as "fuel systems and equipment such as fire extinguishers, cargo heaters, and air conditioners." In that opinion, this Office affirmed that equipment that is an integral part of a motor vehicle is not subject to requirements of the HMR. That opinion, however, does not extend to truck-mounted systems hazardous) during transportation in commerce. designed to facilitate, by pressurization or otherwise, the unloading of cargoes (hazardous or non- From your description of the pressure unloading system, it appears that the receiving tank may conform to requirements in § 173.6(a)(2) for certain Division 2.2 materials of trade. This section specifies that the receiving tank must be manufactured to American Society of Mechanical Engineers (ASME) standards and have a rated capacity of not more than 70 gallons water capacity. In addition, to qualify for the materials of trade exception the vehicle must be operated by a private motor carrier in direct support of a principal business that is other than transportation. If the provisions of § 173.6 are met, then the system is not subject to any other requirements of the HMR. I hope this satisfies your request. Sincerely, Than Thomas G. Allan Senior Transportation Regulations Specialist Office of Hazardous Materials Standards 990224 <<>> • Lik. HMT ASSOCIATES, L.L.C. 99-0224 WASHINGTON, D.C. 20006-350 EA. ALTEMOS (202) 463-3511 PATRICIA A. QUINN GORDON ROUSSEAU FACSIMILE (202) 463-3512 WRITER'S DIRECT DIAL NUMBER (202) 463-3511, Ext. 11 August 18, 1999 Mr. Edward T. Mazzullo Director, Office of Hazardous Materials Standards (DHM-10) Research and Special Programs Administration Department of Transportation Washington, D.C. 20590-0001 Dear Mr. Mazzullo: The enclosed interpretation letter, dated July 26, 1994, confirms that equipment containing • hazardous materials that is an integral part of a motor vehicle, for example (i.e., not limited to) "fuel systems and equipment such as fire extinguishers, cargo heaters, and air conditioners" is not considered to be in commerce, and is not subject to the Hazardous Materials Regulations ("the HMR", 49 CFR Parts 171-180). The letter draws attention to the fact that the Federal Motor Carrier Safety Regulations ("the FMCSR", 49 CFR Parts 390-399) contain specific requirements for certain equipment, such as fuel systems and fire extinguishers. In this regard, it is noted that the FMCSR do not contain specific requirements for the other example of integral equipment cited in the letter and deemed not to be subject to the HMR (i.e., "air conditioners"), although certain general requirements of the FMCSR could be applicable to such systems and their manner of installation on the motor vehicle to which they are integrally attached (e.g., §§ 393.3 and 393.201). Indeed, § 393.3 of the FMCSR provides that "[n]othing contained in this subchapter shall be construed to prohibit the use of additional equipment and accessories, not inconsistent with or prohibited by this subchapter,..." On the basis of the enclosed letter, it may be concluded that equipment and systems containing hazardous materials that are integral to a vehicle are not subject to the HMR, provided <<>> HMT ASSOCIATES, LI.C. Mr. Edward T. Mazzullo August 18, 1999 Page 2 they comply with applicable requirements of the FMCSR (which may be either requirements specific to that system or equipment, or general requirements). The purpose of this letter is to request confirmation of this understanding as it relates to a system containing relatively low pressure compressed air (e.g., not more than 100 psig) that is permanently attached to a commercial motor vehicle. Specifically, the system in question consists of an air compressor and receiver permanently mounted on a motor vehicle. The compressed air is used to drive pneumatic pumps attached to the vehicle, that discharge a non-hazardous liquid from a bulk tank on the vehicle. Compressed air is also used to operate a control system used during the discharge operation. Based on the enclosed letter, I understand that this compressed air system (including the air compressor, receiver, controller and associated piping), which is an integral part of the motor vehicle, is not subject to the HMR when containing compressed air at or above an absolute pressure of 280 kPa (40.6 psia). The system would, however, be required by the FMCSR to comply with any applicable requirements of the FMCSR. Please confirm that my understanding is correct that the compressed air system described above would not be subject to the provisions of the HMR. Thank you for your consideration in this matter. Sincerely, E. A. Altemos Enclosure - **truncated:** false - **body characters:** 5442