{"operation":"document","citation":"25-0049","title":"Boost Oxygen, LLC — Hazardous Materials Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"2026-04-02","effective_on":null,"summary":"25-0049 response to Boost Oxygen, LLC concerning 173.309, 180.209.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-25-0049.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-25-0049.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-25-0049","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2026-04/25-0049.pdf","body":"<<<PAGE 1>>>\n\nU.S. Department\nof Transportation\nPipeline and Hazardous\nMaterials Safety\nAdministration\nApril 2, 2026\nRob Neuner\nChief Executive Officer\nBoost Oxygen, LLC\n125 Old Gate Lane\nMilford, CT 06460\nReference No. 25-0049\n1200 New Jersey Avenue, SE\nWashington, DC 20590\nDear Mr. Neuner:\nThis letter is in response to your April 24, 2025, email requesting clarification of the\nHazardous Materials Regulations (HMR; 49 CFR Parts 171-180) pertaining to the\napplicability of the HMR when shipping oxygen canisters via the U.S. Postal Service\n(USPS).\nWe have paraphrased and answered your questions as follows:\nQ1. Does the Department of Transportation (DOT) have regulatory and/or enforcement\nauthority over the USPS for the filling and transportation of oxygen canisters?\nA1. No. The HMR govern the classification, packaging, marking, shipping\ndocumentation, hazard warning labeling, and placarding for hazardous materials in\ntransportation in commerce. Hazardous materials transported by USPS are not\nsubject to the HMR, see 49 U.S.C. § 5102(9)(b)(i) a. These materials must comply\nwith USPS regulationsb for transporting hazardous materials. Contact USPS\ndirectly for any inquiries concerning U.S. mail shipments of hazardous materials.\nQ2. You state in your letter that you only ship via USPS Ground Advantage—involving\nno private or other carriers. Is Boost Oxygen, LLC subject to fines by DOT if a\nshipment fully complies with USPS regulations versus DOT regulations?\na Federal hazardous materials transportation law (49 U.S.C. 5101, et. seq.)\nb Publication 52, Acceptance of Hazardous, Restricted or Perishable Matter\n\n<<<PAGE 2>>>\n\nA2. No. See A1.\nI hope this information is helpful. Please contact us if we can be of further assistance.\nSincerely,\nAlexander Wolcott\nActing Chief, Regulatory Review and Reinvention Branch\nStandards and Rulemaking Division\n\n<<<PAGE 3>>>\n\nWolcott\n25-0049\nFrom: Baker, Yul (PHMSA)\nTo: Pollack, Arthur (PHMSA)\nSubject: FW: Request for Official Letter of Interpretation\nDate: Thursday, April 24, 2025 11:54:25 AM\nAttachments: image001.png\nimage002.png\nimage003.png\nimage004.png\nimage005.png\nSP-10704 New 2017.pdf\nThank you,\nMr. Yul Brenner Baker Jr.\nTransportation Regulations Specialist, Standards Development\nUSDOT, PHMSA\nPipeline and Hazardous Materials Safety Administration\n1200 New Jersey Ave, SE, Washington, DC, 20590\nOffice number: 717-688-9977\nFrom: Dodd, Alice (PHMSA) <Alice.Dodd@dot.gov>\nSent: Thursday, April 24, 2025 11:48\nTo: Baker, Yul (PHMSA) <yul.baker@dot.gov>\nSubject: FW: Request for Official Letter of Interpretation\nFrom: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>\nSent: Wednesday, April 23, 2025 11:46 AM\nTo: Hazmat Interps <hazmatinterps@dot.gov>\nSubject: FW: Request for Official Letter of Interpretation\nHello Hazmat Interps,\nPlease see attached and below request for letter of interpretation.\nThanks,\nJonathon\nFrom: Rob Neuner <rob@boostoxygen.com>\nSent: Wednesday, April 23, 2025 10:03 AM\nTo: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>\nSubject: RE: Request for Official Letter of Interpretation\nYou don't often get email from rob@boostoxygen.com. Learn why this is important\n\n<<<PAGE 4>>>\n\nCAUTION: This email originated from outside of the Department of Transportation (DOT). Do\nnot click on links or open attachments unless you recognize the sender and know the content is\nsafe.\nHi- My question, name and number was included my previous email, but I will restate\nhere. Hope to hear back from you soon:\n1. Does the Department of Transportation (DOT) have regulatory and/or enforcement\nauthority over the United States Postal Service (USPS) in regards to the filling and\nshipment of our Oxygen canisters?\n2. My question for interpretation is, could my company be fined by the DOT if we fully\ncomplied with the USPS regulations, but not DOT regulations, and only shipped via\nU.S. Parcel Service Ground Advantage (no private or other carriers) at that lesser\npressure (2Q cans = 160 – 180 psi) ?\nThere is a significant discrepancy between what is allowed to be filled and shipped by the\nDOT and what is allowed to be filled and shipped by the USPS in terms of canisters to be\nused (seamed vs. seamless) and pressure ratings.\nYou can read below for context.\nThank you,\nRob Neuner\nCEO\nBoost Oxygen , LLC\n125 Old Gate Lane\nMilford, CT 06460\nTel (203) 619-3616\nOriginal Letter:\nFrom: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>\n\n<<<PAGE 5>>>\n\nSent: Tuesday, April 22, 2025 11:16 AM\nTo: Rob Neuner <rob@boostoxygen.com>\nSubject: Automatic reply: Request for Official Letter of Interpretation\nThank you for contacting the HAZMAT Info Center (HMIC) within the Pipeline and Hazardous\nMaterials Safety Administration (PHMSA). The HMIC assists with the use of the Hazardous Materials\nRegulations (HMR), and provides other services as noted on our website (click here). The information\ncenter is staffed Monday through Friday, 9am-5pm EST. This email acknowledges receipt of your\ninquiry.\nTo better assist you, we ask that you provide your name, a phone number, and a detailed question or\nconcern. You may respond to this email or contact the HMIC by phone at +1 (800) 467-4922 or +1\n(202) 366-4488.\nRegards,\nHazMat InfoCenter Team\nApril 22, 2025\nTo Whom It May Concern:\nWe have a conundrum which we would like an official letter of interpretation so we continue to\ncomply with the laws of shipping.\nMy company, Boost Oxygen, manufacturers, sells and ships compressed Oxygen gas in aluminum\nseamless 2Q containers in compliance with our Special Permit 10704. (attached here).\nCompetitors are popping up shipping in seamed steel containers under pressure (170psi) in violation\nof the Special Permit and also the CFR (49 CFR 173.1. 173.2, 173.3 and others) , but using the U.S.\nPostal Ground Service to do so, as the USPS regulations differ slightly from the DOT regulations, and\nthey allow seamed 2Q containers. The USPS response is included below my signature line.\nSo my question for interpretation is, could my company be fined by the DOT if we complied with the\nUSPS regulations, but not DOT regulations, and only shipped via U.S. Parcel Service Ground Advantage\n(no private or other carriers) at that lesser pressure (2Q cans = 160 – 180 psi) ? Essentially, does the\nDOT have regulatory authority over the USPS in this case? Or no regulatory authority?\nAccording to the USPS below, the 2Q seamed can is permitted to be shipped legally at those pressures\nby the USPS.\nObviously, we want to continue to comply fully. But if competitors are able to legally have a cost\nadvantage (steel is less expensive than aluminum), we would want to reserve the ability to match this.\nIf not, then we would ask for enforcement action.\nThank you for your time and assistance here, our address and the USPS response are below.\nSincerely,\n\n<<<PAGE 6>>>\n\nRob Neuner\nCEO\nUSPS Response:\nThe product ‘Boost Oxygen’ is a nonflammable gas mailable in domestic mail; it is permitted\nwith restrictions via air transportation and permitted via surface transportation. The mailer\nmust follow USPS Packaging Instruction 2B\n(http://pe.usps.gov/text/pub52/pub52apxc_005.htm#ep999646). Please note that a\ncontainer with an internal pressure more than 180 psig at 130°F (55°C) is prohibited\nfrom mailing.\nIf the container meets all requirements for packaging explained in USPS Packaging Instruction\n2B (including internal pressure) the piece will be mailable via air transportation (First-Class\nMail or Priority Mail prices) or via surface transportation ((USPS Marketing Mail, USPS\nGround Advantage)\n\n<<<PAGE 7>>>\n\n1418229 - Boost Oxygen\nRevision Date 12-Oct-2017\n12. ECOLOGICAL INFORMATION\nToxicity\nowen orcare aturaly in the atmosphere. The gas wil be dissipated in rapidly\nEcotoxicity\nThe environmental impact of this product has not been fully investigated.\nPersistence and degradability\nNo information available.\nBioaccumulation potential\nNo information available.\nMobility\nNo information available.\nOther adverse effects\nNo information available.\n13. DISPOSAL CONSIDERATIONS\nWaste treatment methods\nproducts\nWaste from residues/unused\ninterational regulations.\nDispose of content and/or container in accordance with local, regional, national, andfor\nContaminated packaging\nintemational regulations.\nDispose of content and/or container in accordance with local, regional, national, and/or\nUS EPA Waste Number\nD001\nCalifornia Waste Codes\n141\n14. TRANSPORT INFORMATION\nDOTIN- No.\nProper Shipping Name\nAEROSOLS\nUN1950\nSubsidiary class\nHazard Class\n2.2\nPackaging Group\nLTD-QTY\n5.1\nDescription\nNumber\nEmergency Response Guide\n122\nUN195D, AEROSOLS, 2.2 (5.1), LTD- QTY\n3. COMPOSITION/INFORMATION ON INGREDIENTS\nSubstance\nChemical Name Identifiers\nCom\n%\n]LD50/LC5 Classifications According to Regulation/Directive Comment\nOxygen\nCAS:7782-44-7\nEC\nNumber:231-956-\n95.0%\nNDA\nEU CLIP: A A V-01. 65 1 4270, Poss.\nOSH ACCS 202: Ox Gas 1: Press Gas. - Comp.\nNDA\nMaximum\nWHMIS:\nImpurities\n< 0.5%\nDSD/DPD\nEU\nNDA\n: EU\nMhe product contains no substances which at their given concentration, are considered to be hazardous to health.\n\n<<<PAGE 8>>>\n\n342.2 Mailability\n342.21 General\nThe following conditions apply to the mailing of gases:\n1. 2. International Mail. All gases are prohibited.\nDomestic Mail via Air Transportation. Flammable gases in Division 2.1 and toxic gases in\nDivision 2.3 are prohibited. Nonflammable gases in Division 2.2 are generally permitted if the\nmaterial can qualify as a ID8000 material (see 335) and meet the quantity limitations and\npackaging requirements in 342.3 and 342.4.\n3. Domestic Mail via Surface Transportation. Toxic gases in Division 2.3 are prohibited. Flammable\ngases in Division 2.1 and nonflammable gases in Division 2.2 are generally permitted if the\nmaterial can qualify as a Limited Quantity surface material and meet the quantity limitations\nand packaging requirements in 342.3 and 342.4.\nAccording to Pub. 52. 342.23 Mailable Gases\nThe following are examples of mailable gases:\nOxygen, Compressed. Oxygen (UN1072) is a Division 2.2 nonflammable gas and is acceptable in\ndomestic mail only if it can qualify as a Limited Quantity material. The requirements in 342.3 and\nPackaging Instruction 2B in Appendix C must be followed.\n\n<<<PAGE 9>>>\n\nThe main differences between UN1072 and UN1950 products are:\nUN1072 refers to a material that is forbidden in transportation, while UN1950 refers to\naerosols, non-flammable, each not exceeding 1 L capacity.\nUN1072 has a hazard class, while UN1950 does not.\nUN1072 has a proper shipping name, while UN1950 does not.\nUSPS Packaging Instruction 2B\nNonflammable Gases\nA Class 2, Division 2.2 nonflammable gas that qualifies as a Limited Quantity air or Limited\nQuantity surface material is mailable provided that all applicable requirements in 342 are met\nand it is properly packaged as follows.\nProper Shipping Name\nConsumer Commodity.\nID Number\nVarious (see Appendix A).\nMailability\nInternational Mail: Prohibited.\nDomestic Mail: Permitted with restrictions via air transportation and permitted via surface\ntransportation.\nRequired Packaging\nPrimary Receptacle(s)\nThe capacity of an other–than–metal (nonmetal) primary receptacle must be 4 fluid ounces\n(7.22 cubic inches) or less per mailpiece.\nThe capacity of a metal primary receptacle must be 33.8 fluid ounces (1–liter or 61.0 cubic\ninches) or less.\nThe liquid content of the material and the gas must not completely fill the primary receptacle\nat 130° F.\nA DOT 2P container must be used if the internal pressure is from 140 psig to 160 psig at 130° F\n(55° C). A DOT 2Q container must be used if the pressure is from 161 psig to 180 psig at 130° F\n(55° C).\nA container with an internal pressure more than 180 psig at 130° F (55° C) is prohibited from\nmailing.\n\n<<<PAGE 10>>>\n\nThe primary receptacle(s) must be packaged to protect valves and fittings and to ensure\nintegrity during transport.\nThe primary receptacle(s) must have a recessed valve, screw–thread cap, tap closure, or other\nmeans to prevent accidental discharge.\nCushioning Material\nSufficient cushioning material must surround the primary receptacle to absorb shock and\nprevent damage.\nOuter Packaging\nStrong outer packaging that is capable of firmly and securely holding the primary receptacle(s)\nand cushioning material is required.\nMultiple primary receptacles may be securely packed within a single strong outer packaging.\nEach mailpiece must not exceed a total weight of 25 pounds.\nMarking\nThe following labels and text markings must be placed on the address side of the mailpiece\nunless specified in 221.1 and 325.1.\nFor air transportation, mailpieces must bear the DOT Limited Quantity air mark (with the\nsymbol “Y” in the center), an approved DOT Class 9 hazardous material warning label,\nIdentification Number “ID8000,” and the proper shipping name “Consumer Commodity.”\nFor surface transportation, the outer packaging must bear an approved DOT Limited Quantity\nground mark designating surface transportation, prepared under 342.4c. Markings must be\ndurable, legible, and readily visible, and must be applied on at least one side or one end of the\nouter packaging. The border forming the square-on-point must be at least 2 mm in width, and\nthe minimum dimension of each side must be 100 mm, unless the package size requires a\nreduced size marking of no less than 50 mm on each side.\nA complete return and delivery address must be used.\nAIR SURFACE\n\n<<<PAGE 11>>>\n\nDocumentation\nFor air transportation, a mailable, nonflammable gas must have a properly completed shipper‘s\ndeclaration for dangerous goods prepared in triplicate and affixed to the outside of the\nmailpiece.\n342.5 Mailability Rulings\nIn addition to the information required in 215.2 and 324, requests for mailability rulings on\ngases and products containing compressed gases need to include the following information:\n1. 2. 3. 4. 5. 6. Documentation indicating whether or not the contents are a flammable mixture when\ndispersed.\nThe internal pressure within the primary receptacle at 70° F (21° C) and 130° F (55° C).\nDocumentation as to whether or not the liquid contents completely fill the container at 70° F\n(21° C) and 130° F (55° C).\nThe bursting strength of the primary receptacle.\nThe capacity of the primary receptacle and the number of primary receptacles proposed to be\npacked within a single mailpiece.\nThe design methods intended to prevent accidental discharge of the contents.\nDMM 601.1.5 states:\n1.5 Mailer’s Responsibility\nIt is the mailer’s responsibility to refrain from depositing nonmailable matter in the mail. The\nmailer must comply with applicable postal laws and regulations governing mailability and\npreparation for mailing, as well as nonpostal laws and regulations on the possession, treatment,\ntransmission, or transfer of particular matter. Information about USPS standards is available\nfrom postmasters, business mail entry managers, and the PCSC manager (see 608.8.0).\nIf you have any questions, please contact me.\nAundreau J. Anthony\nClassification Specialist |Pricing and Classification Service Center |90 Church St Suite 3100 |New York,\nNY 10007-2951 |Aundreau.J.Anthony@usps.gov\n\n<<<PAGE 12>>>\n\nFrom: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>\nSent: Tuesday, April 22, 2025 1:49 PM\nTo: Rob Neuner <rob@boostoxygen.com>\nSubject: Automatic reply: Request for Official Letter of Interpretation\nThank you for contacting the HAZMAT Info Center (HMIC) within the Pipeline and Hazardous\nMaterials Safety Administration (PHMSA). The HMIC assists with the use of the Hazardous Materials\nRegulations (HMR), and provides other services as noted on our website (click here). The information\ncenter is staffed Monday through Friday, 9am-5pm EST. This email acknowledges receipt of your\ninquiry.\nTo better assist you, we ask that you provide your name, a phone number, and a detailed question or\nconcern. You may respond to this email or contact the HMIC by phone at +1 (800) 467-4922 or +1\n(202) 366-4488.\nRegards,\nHazMat InfoCenter Team\n\n<<<PAGE 13>>>\n\nUS POSTAGE PAID\nPARCEL SELECT\nWASHINGTON DC\nPERMIT NO. 3024\nUSPS Ship\nUSPS PARCEL SELECT\nTINA IL\n13140 ALONDRA BLVD\nCERRITOS\nCA 90703\nSHIP\nLYNN NEUNER\nTO:\nDARIEN CT 068202014\n558 HOYT ST\nYNN NEI\nUSPS TRACKING # USPS Ship\n9261 2903 0323 8854 3402 5177 64\nAOL 22\nMMTD #: 803363209717343589\nPACKAGE ID #: HWCIS2423105766\nRef1:HWCI5242310576\nference No.3: L-WMS-GZY1\nRefere\nince No.4:1 PX4E F9D6(1)\nI)-PX4E-F9D6(1)\nPart # 156697-434\n\n<<<PAGE 14>>>\n\nSeamed Steel\nL Can\ngen\nOXYGEN\nPlus *\nATION FOR USE\na Mak, Protection cap etc.\n(Specification) 1\n00ml\nPapason L.OMPa E0.20MPa.Well\nor reactors to supply oxygen to F\nles aid after oxygenation.\nsealed\nan eply for home and medical\npenting it can be used to prov\ntient\nTe to cove gas Prevent the c\ndead and clean indoor where th\na corage in the places where thi\nrel-\nal 3 Keep it out of the reach\nSoFT\nSet opening the package. 4 Do\n›sable\nof the\nof medicine. ©Dis\nreen Date: See tank\nonalbility of the imp\nOXYGEN\nUS C","truncated":false,"body_characters":16934}