AdvanSix Inc. — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration January 10, 2025 1200 New Jersey Avenue, SE Washington, DC 20590 Larry D. Buffey Dangerous Goods Compliance Leader AdvanSix Inc. Attn: Wenfang Chen 300 Kimball Drive Suite 100 Parsippany, NJ 07054 Reference No. 24-0091 Dear Mr. Buffey: This letter is in response to your September 19, 2024, email and subsequent conversations requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to combustible liquid provisions. Specifically, you ask whether non-bulk, bulk, and reportable quantities of “UN1915, Cyclohexanone, 3, PG III” that meet the reclassification requirements for a combustible liquid would qualify for certain combustible liquid exceptions under § 173.150(f). If “UN1915, Cyclohexanone, 3, PG III” is properly reclassified as a combustible liquid, shipped in non-bulk packaging, and does not meet the definition of a hazardous substance, hazardous waste, or marine pollutant, the exceptions in § 173.150(f)(2) apply when transported by highway or rail—i.e., the requirements in the HMR do not apply. However, if “UN1915, Cyclohexanone, 3, PG III” is properly reclassified as a combustible liquid and is shipped in bulk packaging or meets the definition of a hazardous substance, hazardous waste, or marine pollutant, the provisions in § 173.150(f)(3) apply when shipped by highway or rail—which provide limited exceptions while maintaining certain requirements including, but not limited to, shipping papers, marking of packages, and placarding when applicable. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, Steven Andrews Acting Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division#

Page 224-0091 Jacobson Jones, Jessie Jane CTR (PHMSA) From: INFOCNTR (PHMSA) Sent: Monday, October 7, 2024 2:48 PM To: Dodd, Alice (PHMSA) Cc: Hazmat Interps Subject: FW: Request for a letter of interpretation for Cyclohexanone UN1915 and the Combustible liquid exemption 173.150(f) Follow Up Flag: Follow up Flag Status: Flagged Good Afternoon Alice, See the interpretation request below. Let us know if you need anything else. Best, Aminah From: Buffey, Larry <Larry.Buffey@advansix.com> Sent: Monday, October 7, 2024 12:36 PM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Subject: Re: Request for a letter of interpretation for Cyclohexanone UN1915 and the Combustible liquid exemption 173.150(f) 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. Mailing address: Attn: Larry Buffey 634 SW 12th Street Cape Coral, FL 33991 Larry D. Buffey Jr Principle Product Stewardship Leader; Dangerous Goods Compliance Leader AdvanSix Inc. Office: +1 (973) 526-1633 Business Cell: +1 (810) 931-0280 PCell: +1 (810) 624-9935 1#

Page 3Larry.Buffey@Advansix.com AdvanSix.com From: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Sent: Thursday, September 26, 2024 2:54 PM To: Buffey, Larry <Larry.Buffey@advansix.com> Subject: RE: Request for a letter of interpretation for Cyclohexanone UN1915 and the Combustible liquid exemption 173.150(f) Dear Mr. Buffey, We have received y our request for a written letter of interpretation regardi ng the hazar dous materials regulations (49 CFR Parts 171 -180 ). The hazardous materials regulations are available at the followi ng URL: https: //www. e cfr. gov/cgi -bin/text-idx?SID=1d4 9a3b1 37cb1b6fc452 51074 e634b4 4&t pl=/ecfrbr owse/Title49 /49tab_ 02. tpl ZjQcmQRYFpfptBa nnerStart This Message Is From an External Sender This message came from outside AdvanSix Do not click on links or open attachments without verifying sender and URLs Report Suspicious ZjQcmQRYFpfptBa nnerE nd Dear Mr. Buffey, We have received your request for a written letter of interpretation regarding the hazardous materials regulations (49 CFR Parts 171-180). The hazardous materials regulations are available at the following URL: https://www.ecfr.gov/cgi-bin/text- idx?SID=1d49a3b137cb1b6fc45251074e634b44&tpl=/ecfrbrowse/Title49/49tab_02.tpl [ecfr.gov] However, before we can submit your request for processing, please respond to this email with:  Physical Mailing Address Sincerely, Aminah, Hazardous Materials Specialist An e-mail response from this office is considered informal guidance. Formal guidance may be requested in accordance with 49 CFR 105.20. https://www.phmsa.dot.gov/standards- rulemaking/hazmat/hazardous-materials-information-center [phmsa.dot.gov] From: Buffey, Larry <Larry.Buffey@advansix.com> Sent: Thursday, September 19, 2024 8:47 AM To: PHMSA HM InfoCenter <PHMSAHMInfoCenter@dot.gov> Subject: Request for a letter of interpretation for Cyclohexanone UN1915 and the Combustible liquid exemption 173.150(f) 2#

Page 4CAUTION: 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. Good morning, MY name is Larry Buffey and I work for a chemical manufacturer. We produce and ship Cyclohexanone globally. We have recently taken advantage of the ability to reclassify Cyclohexanone under the 173.150 (f)Exemption. We ship in Bulk and Non-bulk. We have a drumming facility that is expressing the concern that the non-bulk packaging still requires the Combustible Liquid Marking on the Drum. The question is if Cyclohexanone is still considered a hazardous material or not. and whether the Non-bulk packaging is required to display markings. Here is how AdvanSix understand the regulation as follows, UN1915, Cyclohexanone is a flammable liquid with a FP of 44°C / BP 155.6°C (according to the our SDS [advansix.store]), and it meets the classification criteria as a hazardous material (PG III). It is authorized in the hazmat table to be shipped under the exceptions of §173.150. That allows Nadone to be shipped as a limited quantity in inner packagings up to 5L each and it provides the option of reclassifying it to a combustible liquid. As you know a flammable liquid MAY be reclassified as a combustible liquid for domestic ground transportation if the flash point is ≥38°C. This provides an exemption from marking, labeling, UN specification packaging and shipping papers. It is an option. UN1915 shipped under an exception (combustible liquid) is still a hazardous material but it can be shipped as “not regulated”. However, if it is transported by air or vessel, it must be transported as UN1915, Cyclohexanone as combustible liquid is not recognized by those modes of transport. I am requesting a formal letter of interpretation on this topic. Please contact me for any question you may have regarding this. Larry D. Buffey Jr Principle Product Stewardship Leader; Dangerous Goods Compliance Leader AdvanSix Inc. Office: +1 (973) 526-1633 Business Cell: +1 (810) 931-0280 3#

Page 5PCell: +1 (810) 624-9935 Larry.Buffey@Advansix.com AdvanSix.com 4#