Betts Industries, Inc. — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 July 2, 2025 David J. Adams Director of Design Engineering Betts Industries, Inc. 1800 Pennsylvania Ave. West Warren, PA 16365 Reference No. 25-0043 Dear Mr. Adams: This letter is in response to your April 10, 2025 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to a cargo tank motor vehicle (CTMV). Specifically, you ask about the use of an engineered copolymer as the material of construction for certain parts of a CTMV. We have paraphrased and answered your questions as follows: Q1. Does the requirement for the use of nonmetallic materials outlined in § 178.345-9(h) apply to the body of a pressure relief device (PRD), such as a normal vent used on a Department of Transportation (DOT) 406 CTMV? A1. No. Section § 178.345-9(h) is applicable for components outboard of the lading retention system and does not apply to PRDs. PRD requirements are generally outlined in § 178.345-10 for DOT 400 series CTMVs, and further specified in §§ 178.346-3, 178.347-4, and 178.348-4 for DOT 406, DOT 407, and DOT 412 CTMVs, respectively. Q2. Does the HMR prohibit the use of a high-performance engineered copolymer as the material of construction for the body of a normal vent on a DOT 406 CTMV?#

Page 2A2. No. The HMR do not specify requirements or restrictions pertaining to materials of construction for PRDs on DOT 406 CTMVs; however, the pressure relief system— including normal vents—must meet the performance requirements in §§ 178.345 and 178.346, as well as the general packaging compatibility requirement in § 173.24 regarding the use of a packaging and its lading. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, Dirk Der Kinderen Chief, Standards Development Branch Standards and Rulemaking Division#

Page 3Casey, C. 25-0043 From: INFOCNTR (PHMSA) To: Dodd, Alice (PHMSA) Cc: Hazmat Interps; Baker, Yul (PHMSA) Subject: FW: Request for Interpretation 49CFR§178.345-9 Date: Thursday, April 10, 2025 10:48:28 Hi Alice, Please see the below interpretation request. Let me know if you need anything, -Breanna From: David J. Adams <dadams@bettsind.com> Sent: Thursday, April 10, 2025 9:23 AM To: PHMSA Website Manager <PHMSAWebsiteManager@dot.gov> Cc: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Subject: Request for Interpretation 49CFR§178.345-9 Some people who received this message don't often get email from dadams@bettsind.com. Learn why this is important 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. To Whom It May Concern, I would like to request a regulation interpretation or clarification. Current regulation reads: 49CFR§178.345-9 Pumps, piping, hoses and connections. (h) Use of a nonmetallic pipe, valve or connection that is not as strong and heat resistant as the cargo tank material is authorized only if such attachment is located outboard of the lading retention system. Specific requests for interpretation: 1. 49CFR§178.345-9(h) addresses the material restriction for nonmetallic pipe, valve or connection. Does the material restriction mandated by 49CFR§178.345-9(h) also apply to the material used for the body of a pressure relief device such as a normal vent used on a DOT 406 cargo Tank? 2. Are there any other sections of code that restrict the use of high-performance#

Page 4engineered copolymer as the material of construction for a normal vent body for use on DOT 406 cargo tank? Thank you for your time and consideration. Best regards, David J. Adams Director of Design Engineering dadams@bettsind.com P 814-723-1250 Ex. 136 Betts Industries, Inc. Betts Industries, Inc. 1800 Pennsylvania Ave W., Warren, PA 16365 **** Betts Industries, Inc. Email Notification **** This e-mail is only intended for the person(s) to whom it is addressed and may contain confidential information. Unless stated to the contrary, any opinions or comments are personal to the writer and do not represent the official view of the company. If you have received this e-mail in error, please notify us immediately by reply e-mail and then delete this message from your system. Please do not copy it or use it for any purposes, or disclose its contents to any other person. Thank you for your cooperation.#