Ashimori — Hazardous Materials Safety Interpretation

Page 11200 New Jersey Avenue, SE Washington, DC 20590 U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration July 8, 2026 Soon-Ae Shim Senior Manager Ashimori (Sinpyeong-ri) 134 Dowon-ro, Jijeong-myeon, Wonju-si Gangwon-do, Korea 26351 Reference No. 25-0157 Dear Ms. Shim: This letter is in response to your December 3, 2025 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to safety devices. Specifically, you ask whether the testing exception in 49 CFR 172.102, Special Provision 160 applies to seatbelt pretensioners that contain a tested airbag inflator. No. Special Provision 160 states that “if the airbag inflator unit satisfactorily passes the series 6(c) test, it is not necessary to repeat the test on the airbag module.” This exception is not extended to seatbelt pretensioners even if they use a tested inflator. For a hazardous material assigned Special Provision 160, the series 6(c) test must be repeated for other devices, except on the airbag module when the airbag inflator has already passed the test. Further, 49 CFR 173.166(d)(2) specifies an additional requirement, in that the airbag modules still must be examined for situations where the airbag inflator was approved as Class 9 but depended upon packaging or other special means specified by the authorized testing agency to obtain this classification. This regulatory requirement is necessary to separately assess the hazards of the module and whether it also requires a specific packaging configuration to meet the criteria for Class 9. 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 2Jacobson, N. 25-0157 From: INFOCNTR (PHMSA) To: Baker, Yul (PHMSA) Cc: Hazmat Interps Subject: FW: Request for Clarification on Special Provision 160 - Test Series 6(c) Date: Wednesday, December 3, 2025 12:23:41 Hi Yul, Please see the below interpretation request. Let us know if you need anything, -Breanna From: PHMSA Pipelinesafety <PHMSA.Pipelinesafety@dot.gov> Sent: Wednesday, December 3, 2025 9:27 AM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Subject: FW: Request for Clarification on Special Provision 160 - Test Series 6(c) Good morning, Please find the inquiry below. Thank you! Jessica From: Soonae.Shim <soonae_shim@ashimori.co.kr> Sent: Wednesday, December 3, 2025 4:19 AM To: PHMSA Pipelinesafety <PHMSA.Pipelinesafety@dot.gov>; hmregs@dot.gov; phmsa-info@dot.gov Subject: Request for Clarification on Special Provision 160 - Test Series 6(c) soonae_shim@ashimori.co.kr에게서 전자 메일을 받지 못하는 경우가 많습니다. 이 문제가 중요한 이유 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. Dear PHMSA Hazardous Materials Information Center, I hope this message finds you well. We are a manufacturer of airbag and seatbelt modules in South Korea. I am writing to request an official interpretation regarding 49 CFR 172.102, Special Provision 160. According to the regulation, safety devices such as air bag inflators, air bag modules, seat-belt pretensioners, and p yromechanical devices containing Class 1 (explosive) materials must be tested in accordance with Test Series 6(c) of Part I of the UN Manual of Tests and Criteria. The provision further states that if the air bag inflator unit satisfactorily passes the Series 6(c) test, it is not necessar y to repeat the test on the air bag module. I have the following questions regarding this provision: l If an air bag inflator has successfully passed the Series 6(c) test, does this exemption apply only to the air ba g module, or does it also extend to seat-belt pretensioners use the same inflator? l In other words, must the airbag module that utilizes the inflator undergo the Series 6(c) test again?#

Page 3l Do seatbelt pretensioners need to undergo a separate Series 6(c) test, or can they be exempted if the inflato r has already passed the test? Your clarification on this matter would be greatly appreciated to ensure our compliance with the Hazardous Materi als Regulations. Thank you for your assistance. ~eou ~~DHLP~i SOON-AE SHIM SENIOR MANAGER E£~~~2.rn1 I Project Management Team 070-7004 -5584(241) 033-7 4 2-6624 010-3198-8698 soonae shim@.ashim ori.c o.kr _ 26351 Yf!£ f,!-:,..q XI~~ £fl~ 134 <~'l!i!.ll (Sinpyeong-n) 134 Dowon-ro, J11eon9-myeon, Won1u-si, Gangwon-do, 26351, Korea The FOCUS Method W11h a Fundamental m ndset, we Overcome ourselves 71~~~2.£ , AA§!- ~ -St.'.il Challenge ti~~OI £~3!-01 ano Upgrade . ~~~t;i;t, Let's Start now I Xl ~ A l~~:q,#