Commercial Vehicle Safety Alliance — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 September 18, 2025 Collin B. Mooney, MPA, CAE Executive Director Commercial Vehicle Safety Alliance 99 M Street, SE, Suite 1025 Washington, DC 20003 Reference No. 25-0056 Dear Mr. Mooney: This letter is in response to your email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the marking requirements for nurse tanks. In your email, you state that § 173.315(m) allows for the use of a cargo tank, commonly known as a nurse tank, to transport anhydrous ammonia for agricultural purposes. You further state that § 173.315(m)(1)(vii) allows for the nurse tanks not to be marked or placarded on one end if that end contains valves, fittings, regulators or gauges when those appurtenances prevent the markings and placard from being properly placed and visible. You contend that there is confusion because § 172.328(b) states that “except for certain nurse tanks which must be marked as specified in § 173.315(m), each cargo tank transporting a Class 2 material subject to the HMR must be marked, in lettering no less than 50 mm (2.0 inches), on each side and each end with the proper shipping name or appropriate common name.” Lastly, you state that the phrase, “except for certain nurse tanks” leads to confusion for enforcement personnel because it implies that certain nurse tanks require the proper shipping name or common name marking while others may not. You ask for clarification on whether this is the case. The phrase “except for certain nurse tanks” refers to those nurse tanks meeting the singular exception provided for marking in § 173.315(m)(1)(vii)—those nurse tanks where valves, fittings, regulators or gauges prevent the markings and placard from being properly placed and#

Page 2visible on one end. In that case, the affected end need not be placarded or marked. Otherwise, all nurse tanks must be marked with the proper shipping name or common name on each side and each end as required by § 172.328(b). I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, Alexander Wolcott Acting Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division#

Page 325-0056 Larson Pollack, Arthur (PHMSA) From: Adrienne Gildea <adrienne.gildea@cvsa.org> Sent: Thursday, May 30, 2024 3:35 PM To: Kelley, Shane (PHMSA) Cc: Collin Mooney; Bill Reese Subject: Letter to PHMSA Requesting Interpretation Regarding PSN Display on Nurse Tanks Attachments: Letter to PHMSA Requesting Interpretation Regarding PSN Display on Nurse Tanks.pdf Good a ernoon Mr. Kelley, A ached, please find a le er reques ng clarifica on regarding the requirements for marking the proper shipping name on a nurse tank. We appreciate your considera on of this request. Thank you, Adrienne Adrienne Gildea, CAE Deputy Execu ve Director adrienne.gildea@cvsa.org Direct: 202-998-1009 Mobile: 202-213-5890 99 M Street, SE, Suite 1025 Washington, DC 20003 Phone: 202-998-1002 www.cvsa.org To help protect y ou Microsoft Office pre automatic download from the Internet. facebook To help protect y ou Microsoft Office pre automatic download from the Internet. twitter To help protect y ou Microsoft Office pre automatic download from the Internet. linkedin To help protect y ou Microsoft Office pre automatic download from the Internet. vimeo 1#

Page 4May 30, 2024 Mr. Shane Kelley Director, Standards and Rulemaking Division (PHH-10) U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Ave. SE Washington, DC 20590 RE: Clarification of the requirements in § 172.328(b)(1) that the proper shipping name be marked on a nurse tank Dear Director Kelley, The Commercial Vehicle Safety Alliance (CVSA) requests clarification from the Pipeline and Hazardous Materials Safety Administration (PHMSA) regarding the requirements for marking the proper shipping name on a nurse tank. Currently, § 173.315(m) allows for the use of a cargo tank, commonly known as a nurse tank, to transport anhydrous ammonia for agricultural purposes. Further, § 173.315(m)(1)(vii) requires these tanks be operated in conformance with 49 Code of Federal Regulations Part 172, with the exception that shipping papers are not required and the end of a tank that contains valves, fittings, regulators or gauges need not be marked or placarded. However, § 172.328(b) requires that “except for certain nurse tanks…” the proper shipping name or common name be marked on a nurse tank transporting a Class 2 material. This wording has led to confusion as to whether or not the proper shipping name is required to be marked on a nurse tank. Further, the language “certain nurse tanks” leads to additional confusion regarding whether it should be interpreted that the proper shipping name is required on some nurse tanks but not required on others. CVSA is a nonprofit organization comprised of local, state, provincial, territorial and federal commercial motor vehicle safety officials and industry representatives. The Alliance aims to prevent commercial motor vehicle crashes, injuries and fatalities and believes that collaboration between government and industry improves road safety and saves lives. Our mission is to improve commercial motor vehicle safety and enforcement by providing guidance, education and advocacy for enforcement and industry across North America.#

Page 5Request CVSA requests that PHMSA issue guidance on whether § 172.328(b) requires the proper shipping name or common name to be marked on all nurse tanks and clarify the meaning of the term “certain nurse tanks” as used in that section. Justification As noted above, there is confusion regarding the requirement for nurse tanks transporting anhydrous ammonia to be marked with the proper shipping name, and whether this requirement applies to all nurse tanks or not. CVSA has a cooperative agreement with the Federal Motor Carrier Safety Administration to provide required certification training for state and local law enforcement officers in the proper procedures to conduct roadside inspections of commercial motor vehicles. To ensure the regulations are being enforced correctly and inspectors are receiving accurate training instruction regarding marking requirements for nurse tanks transporting anhydrous ammonia, CVSA is requesting clarification to the questions posed above. PHMSA’s guidance on this matter will ensure CVSA provides the correct guidance to the state and local officials conducting roadside inspections. CVSA works to closely monitor, evaluate and identify potentially unsafe transportation processes and procedures as well as to help facilitate and implement best practices for enhancing safety on our roadways. Commercial motor vehicle safety continues to be a challenge and we need the involvement of all affected parties to help us better understand these issues and put into place practical solutions. We appreciate the agency’s commitment to safety and stakeholder involvement. If you have further questions or comments, please do not hesitate to contact me at 202-998-1008 or collin.mooney@cvsa.org. Respectfully, Collin B. Mooney, MPA, CAE Executive Director Commercial Vehicle Safety Alliance 2#