Boost Oxygen, LLC — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration April 2, 2026 Rob Neuner Chief Executive Officer Boost Oxygen, LLC 125 Old Gate Lane Milford, CT 06460 Reference No. 25-0049 1200 New Jersey Avenue, SE Washington, DC 20590 Dear Mr. Neuner: This letter is in response to your April 24, 2025, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) pertaining to the applicability of the HMR when shipping oxygen canisters via the U.S. Postal Service (USPS). We have paraphrased and answered your questions as follows: Q1. Does the Department of Transportation (DOT) have regulatory and/or enforcement authority over the USPS for the filling and transportation of oxygen canisters? A1. No. The HMR govern the classification, packaging, marking, shipping documentation, hazard warning labeling, and placarding for hazardous materials in transportation in commerce. Hazardous materials transported by USPS are not subject to the HMR, see 49 U.S.C. § 5102(9)(b)(i) a. These materials must comply with USPS regulationsb for transporting hazardous materials. Contact USPS directly for any inquiries concerning U.S. mail shipments of hazardous materials. Q2. You state in your letter that you only ship via USPS Ground Advantage—involving no private or other carriers. Is Boost Oxygen, LLC subject to fines by DOT if a shipment fully complies with USPS regulations versus DOT regulations? a Federal hazardous materials transportation law (49 U.S.C. 5101, et. seq.) b Publication 52, Acceptance of Hazardous, Restricted or Perishable Matter#

Page 2A2. No. See A1. 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 3Wolcott 25-0049 From: Baker, Yul (PHMSA) To: Pollack, Arthur (PHMSA) Subject: FW: Request for Official Letter of Interpretation Date: Thursday, April 24, 2025 11:54:25 AM Attachments: image001.png image002.png image003.png image004.png image005.png SP-10704 New 2017.pdf Thank you, Mr. Yul Brenner Baker Jr. Transportation Regulations Specialist, Standards Development USDOT, PHMSA Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Ave, SE, Washington, DC, 20590 Office number: 717-688-9977 From: Dodd, Alice (PHMSA) <Alice.Dodd@dot.gov> Sent: Thursday, April 24, 2025 11:48 To: Baker, Yul (PHMSA) <yul.baker@dot.gov> Subject: FW: Request for Official Letter of Interpretation From: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Sent: Wednesday, April 23, 2025 11:46 AM To: Hazmat Interps <hazmatinterps@dot.gov> Subject: FW: Request for Official Letter of Interpretation Hello Hazmat Interps, Please see attached and below request for letter of interpretation. Thanks, Jonathon From: Rob Neuner <rob@boostoxygen.com> Sent: Wednesday, April 23, 2025 10:03 AM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Subject: RE: Request for Official Letter of Interpretation You don't often get email from rob@boostoxygen.com. Learn why this is important#

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. Hi- My question, name and number was included my previous email, but I will restate here. Hope to hear back from you soon: 1. Does the Department of Transportation (DOT) have regulatory and/or enforcement authority over the United States Postal Service (USPS) in regards to the filling and shipment of our Oxygen canisters? 2. My question for interpretation is, could my company be fined by the DOT if we fully complied with the USPS regulations, but not DOT regulations, and only shipped via U.S. Parcel Service Ground Advantage (no private or other carriers) at that lesser pressure (2Q cans = 160 – 180 psi) ? There is a significant discrepancy between what is allowed to be filled and shipped by the DOT and what is allowed to be filled and shipped by the USPS in terms of canisters to be used (seamed vs. seamless) and pressure ratings. You can read below for context. Thank you, Rob Neuner CEO Boost Oxygen , LLC 125 Old Gate Lane Milford, CT 06460 Tel (203) 619-3616 Original Letter: From: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>#

Page 5Sent: Tuesday, April 22, 2025 11:16 AM To: Rob Neuner <rob@boostoxygen.com> Subject: Automatic reply: Request for Official Letter of Interpretation Thank you for contacting the HAZMAT Info Center (HMIC) within the Pipeline and Hazardous Materials Safety Administration (PHMSA). The HMIC assists with the use of the Hazardous Materials Regulations (HMR), and provides other services as noted on our website (click here). The information center is staffed Monday through Friday, 9am-5pm EST. This email acknowledges receipt of your inquiry. To better assist you, we ask that you provide your name, a phone number, and a detailed question or concern. You may respond to this email or contact the HMIC by phone at +1 (800) 467-4922 or +1 (202) 366-4488. Regards, HazMat InfoCenter Team April 22, 2025 To Whom It May Concern: We have a conundrum which we would like an official letter of interpretation so we continue to comply with the laws of shipping. My company, Boost Oxygen, manufacturers, sells and ships compressed Oxygen gas in aluminum seamless 2Q containers in compliance with our Special Permit 10704. (attached here). Competitors are popping up shipping in seamed steel containers under pressure (170psi) in violation of the Special Permit and also the CFR (49 CFR 173.1. 173.2, 173.3 and others) , but using the U.S. Postal Ground Service to do so, as the USPS regulations differ slightly from the DOT regulations, and they allow seamed 2Q containers. The USPS response is included below my signature line. So my question for interpretation is, could my company be fined by the DOT if we complied with the USPS regulations, but not DOT regulations, and only shipped via U.S. Parcel Service Ground Advantage (no private or other carriers) at that lesser pressure (2Q cans = 160 – 180 psi) ? Essentially, does the DOT have regulatory authority over the USPS in this case? Or no regulatory authority? According to the USPS below, the 2Q seamed can is permitted to be shipped legally at those pressures by the USPS. Obviously, we want to continue to comply fully. But if competitors are able to legally have a cost advantage (steel is less expensive than aluminum), we would want to reserve the ability to match this. If not, then we would ask for enforcement action. Thank you for your time and assistance here, our address and the USPS response are below. Sincerely,#

Page 6Rob Neuner CEO USPS Response: The product ‘Boost Oxygen’ is a nonflammable gas mailable in domestic mail; it is permitted with restrictions via air transportation and permitted via surface transportation. The mailer must follow USPS Packaging Instruction 2B (http://pe.usps.gov/text/pub52/pub52apxc_005.htm#ep999646). Please note that a container with an internal pressure more than 180 psig at 130°F (55°C) is prohibited from mailing. If the container meets all requirements for packaging explained in USPS Packaging Instruction 2B (including internal pressure) the piece will be mailable via air transportation (First-Class Mail or Priority Mail prices) or via surface transportation ((USPS Marketing Mail, USPS Ground Advantage)#

Page 71418229 - Boost Oxygen Revision Date 12-Oct-2017 12. ECOLOGICAL INFORMATION Toxicity owen orcare aturaly in the atmosphere. The gas wil be dissipated in rapidly Ecotoxicity The environmental impact of this product has not been fully investigated. Persistence and degradability No information available. Bioaccumulation potential No information available. Mobility No information available. Other adverse effects No information available. 13. DISPOSAL CONSIDERATIONS Waste treatment methods products Waste from residues/unused interational regulations. Dispose of content and/or container in accordance with local, regional, national, andfor Contaminated packaging intemational regulations. Dispose of content and/or container in accordance with local, regional, national, and/or US EPA Waste Number D001 California Waste Codes 141 14. TRANSPORT INFORMATION DOTIN- No. Proper Shipping Name AEROSOLS UN1950 Subsidiary class Hazard Class 2.2 Packaging Group LTD-QTY 5.1 Description Number Emergency Response Guide 122 UN195D, AEROSOLS, 2.2 (5.1), LTD- QTY 3. COMPOSITION/INFORMATION ON INGREDIENTS Substance Chemical Name Identifiers Com % ]LD50/LC5 Classifications According to Regulation/Directive Comment Oxygen CAS:7782-44-7 EC Number:231-956- 95.0% NDA EU CLIP: A A V-01. 65 1 4270, Poss. OSH ACCS 202: Ox Gas 1: Press Gas. - Comp. NDA Maximum WHMIS: Impurities < 0.5% DSD/DPD EU NDA : EU Mhe product contains no substances which at their given concentration, are considered to be hazardous to health.#

Page 8342.2 Mailability 342.21 General The following conditions apply to the mailing of gases: 1. 2. International Mail. All gases are prohibited. Domestic Mail via Air Transportation. Flammable gases in Division 2.1 and toxic gases in Division 2.3 are prohibited. Nonflammable gases in Division 2.2 are generally permitted if the material can qualify as a ID8000 material (see 335) and meet the quantity limitations and packaging requirements in 342.3 and 342.4. 3. Domestic Mail via Surface Transportation. Toxic gases in Division 2.3 are prohibited. Flammable gases in Division 2.1 and nonflammable gases in Division 2.2 are generally permitted if the material can qualify as a Limited Quantity surface material and meet the quantity limitations and packaging requirements in 342.3 and 342.4. According to Pub. 52. 342.23 Mailable Gases The following are examples of mailable gases: Oxygen, Compressed. Oxygen (UN1072) is a Division 2.2 nonflammable gas and is acceptable in domestic mail only if it can qualify as a Limited Quantity material. The requirements in 342.3 and Packaging Instruction 2B in Appendix C must be followed.#

Page 9The main differences between UN1072 and UN1950 products are: UN1072 refers to a material that is forbidden in transportation, while UN1950 refers to aerosols, non-flammable, each not exceeding 1 L capacity. UN1072 has a hazard class, while UN1950 does not. UN1072 has a proper shipping name, while UN1950 does not. USPS Packaging Instruction 2B Nonflammable Gases A Class 2, Division 2.2 nonflammable gas that qualifies as a Limited Quantity air or Limited Quantity surface material is mailable provided that all applicable requirements in 342 are met and it is properly packaged as follows. Proper Shipping Name Consumer Commodity. ID Number Various (see Appendix A). Mailability International Mail: Prohibited. Domestic Mail: Permitted with restrictions via air transportation and permitted via surface transportation. Required Packaging Primary Receptacle(s) The capacity of an other–than–metal (nonmetal) primary receptacle must be 4 fluid ounces (7.22 cubic inches) or less per mailpiece. The capacity of a metal primary receptacle must be 33.8 fluid ounces (1–liter or 61.0 cubic inches) or less. The liquid content of the material and the gas must not completely fill the primary receptacle at 130° F. A DOT 2P container must be used if the internal pressure is from 140 psig to 160 psig at 130° F (55° C). A DOT 2Q container must be used if the pressure is from 161 psig to 180 psig at 130° F (55° C). A container with an internal pressure more than 180 psig at 130° F (55° C) is prohibited from mailing.#

Page 10The primary receptacle(s) must be packaged to protect valves and fittings and to ensure integrity during transport. The primary receptacle(s) must have a recessed valve, screw–thread cap, tap closure, or other means to prevent accidental discharge. Cushioning Material Sufficient cushioning material must surround the primary receptacle to absorb shock and prevent damage. Outer Packaging Strong outer packaging that is capable of firmly and securely holding the primary receptacle(s) and cushioning material is required. Multiple primary receptacles may be securely packed within a single strong outer packaging. Each mailpiece must not exceed a total weight of 25 pounds. Marking The following labels and text markings must be placed on the address side of the mailpiece unless specified in 221.1 and 325.1. For air transportation, mailpieces must bear the DOT Limited Quantity air mark (with the symbol “Y” in the center), an approved DOT Class 9 hazardous material warning label, Identification Number “ID8000,” and the proper shipping name “Consumer Commodity.” For surface transportation, the outer packaging must bear an approved DOT Limited Quantity ground mark designating surface transportation, prepared under 342.4c. Markings must be durable, legible, and readily visible, and must be applied on at least one side or one end of the outer packaging. The border forming the square-on-point must be at least 2 mm in width, and the minimum dimension of each side must be 100 mm, unless the package size requires a reduced size marking of no less than 50 mm on each side. A complete return and delivery address must be used. AIR SURFACE#

Page 11Documentation For air transportation, a mailable, nonflammable gas must have a properly completed shipper‘s declaration for dangerous goods prepared in triplicate and affixed to the outside of the mailpiece. 342.5 Mailability Rulings In addition to the information required in 215.2 and 324, requests for mailability rulings on gases and products containing compressed gases need to include the following information: 1. 2. 3. 4. 5. 6. Documentation indicating whether or not the contents are a flammable mixture when dispersed. The internal pressure within the primary receptacle at 70° F (21° C) and 130° F (55° C). Documentation as to whether or not the liquid contents completely fill the container at 70° F (21° C) and 130° F (55° C). The bursting strength of the primary receptacle. The capacity of the primary receptacle and the number of primary receptacles proposed to be packed within a single mailpiece. The design methods intended to prevent accidental discharge of the contents. DMM 601.1.5 states: 1.5 Mailer’s Responsibility It is the mailer’s responsibility to refrain from depositing nonmailable matter in the mail. The mailer must comply with applicable postal laws and regulations governing mailability and preparation for mailing, as well as nonpostal laws and regulations on the possession, treatment, transmission, or transfer of particular matter. Information about USPS standards is available from postmasters, business mail entry managers, and the PCSC manager (see 608.8.0). If you have any questions, please contact me. Aundreau J. Anthony Classification Specialist |Pricing and Classification Service Center |90 Church St Suite 3100 |New York, NY 10007-2951 |Aundreau.J.Anthony@usps.gov#

Page 12From: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Sent: Tuesday, April 22, 2025 1:49 PM To: Rob Neuner <rob@boostoxygen.com> Subject: Automatic reply: Request for Official Letter of Interpretation Thank you for contacting the HAZMAT Info Center (HMIC) within the Pipeline and Hazardous Materials Safety Administration (PHMSA). The HMIC assists with the use of the Hazardous Materials Regulations (HMR), and provides other services as noted on our website (click here). The information center is staffed Monday through Friday, 9am-5pm EST. This email acknowledges receipt of your inquiry. To better assist you, we ask that you provide your name, a phone number, and a detailed question or concern. You may respond to this email or contact the HMIC by phone at +1 (800) 467-4922 or +1 (202) 366-4488. Regards, HazMat InfoCenter Team#

Page 13US POSTAGE PAID PARCEL SELECT WASHINGTON DC PERMIT NO. 3024 USPS Ship USPS PARCEL SELECT TINA IL 13140 ALONDRA BLVD CERRITOS CA 90703 SHIP LYNN NEUNER TO: DARIEN CT 068202014 558 HOYT ST YNN NEI USPS TRACKING # USPS Ship 9261 2903 0323 8854 3402 5177 64 AOL 22 MMTD #: 803363209717343589 PACKAGE ID #: HWCIS2423105766 Ref1:HWCI5242310576 ference No.3: L-WMS-GZY1 Refere ince No.4:1 PX4E F9D6(1) I)-PX4E-F9D6(1) Part # 156697-434#

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