{"operation":"document","citation":"25-0084","title":"Texas Department of Public Safety — Hazardous Materials Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"2025-12-08","effective_on":null,"summary":"25-0084 response to Texas Department of Public Safety concerning 171.8, 172.102, 173.241, 173.29.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-25-0084.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-25-0084.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-25-0084","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2025-12/250084.pdf","body":"<<<PAGE 1>>>\n\n1200 New Jersey Avenue, SE\nWashington, DC 20590\nU.S. Department\nof Transportation\nPipeline and Hazardous\nMaterials Safety\nAdministration\nDecember 8, 2025\nDustin Henderson\nCVE-Corporal IV\nRadiation/Nuclear Threat Detection Unit\nTexas Department of Public Safety\n1600 West Loop 306\nSan Angelo, TX 76904\nReference No. 25-0084\nDear Mr. Henderson:\nThis letter is in response to your June 23, 2025 email requesting clarification of the Hazardous\nMaterials Regulations (HMR; 49 CFR Parts 171-180) applicable to bulk containers commonly\nknown in industry as “frac tanks.” Specifically, you ask for clarification regarding the use of frac\ntanks for the transportation of “NA1993, Diesel fuel, 3, Packing Group (PG) III.”\nWe have paraphrased and answered your questions as follows:\nQ1. Does a frac tank meet the definition of a portable tank in accordance with § 171.8?\nA1. No. Frac tanks do not meet the definition of a portable tank and the term “frac tank” is\nnot defined in § 171.8. In addition, the pictures provided in the initial request do not\ndisplay the characteristics (e.g., skids, mountings, etc.) to identify these packagings as\nportable tanks; however, they may qualify as non-DOT specification cargo tank motor\nvehicles.\nQ2. If a frac tank meets the definition of a portable tank, is “NA1993, Diesel fuel, 3, PG III”\nauthorized for transport in a frac tank in accordance with § 173.241(c)?\nA2. Frac tanks do not meet the definition of a portable tank; however, “NA1993, Diesel fuel,\n3, PG III” may be transported in a non-DOT specification cargo tank motor vehicle\nsuitable for the transport of liquids. It is the offeror’s responsibility to determine the flash\npoint of the hazardous material1, package compliance, and all requirements of the HMR\nare met prior to the shipment being offered for transportation.\n1 § 172.102(c)(3), Special Provision B1.\n\n<<<PAGE 2>>>\n\nQ3. Can “NA1993, Diesel fuel, 3, PG III” be transported in a frac tank as residue?\nA3. Yes. An empty packaging containing only the residue of a hazardous material shall be\noffered for transportation and transported in the same manner as when it previously\ncontained a greater quantity of that hazardous material.2\nQ4. Can “NA1993, Diesel fuel, 3, PG III” be transported in a frac tank, while the frac tank is\nlocated on a trailer?\nA4. Yes. The HMR does not prohibit frac tanks from being transported on trailers. However,\nit is the offeror’s responsibility to ensure the hazardous material is properly classified,\nand the package is offered for transportation in accordance with the HMR.\nQ5. Would a frac tank qualify as a “tank” for purposes of a commercial driver’s license\n(CDL) and require the driver to obtain an endorsement?\nA5. The endorsement requirements for a CDL are under the purview of the Federal Motor\nCarrier Safety Administration (FMCSA)—see 49 CFR Part 383. FMCSA is the lead\nFederal government agency responsible for regulating and providing safety oversight\nof commercial motor vehicles. You may wish to contact the FMCSA regarding\nclarification of any applicable CDL endorsement requirements.\nI hope this information is helpful. Please contact us if we can be of further assistance.\nSincerely,\nDirk DerKinderen\nChief, Standards and Development Branch\nStandards and Rulemaking Division\n2 § 173.29.\n\n<<<PAGE 3>>>\n\nHorne, T.\n25-0084\nFrom: INFOCNTR (PHMSA)\nTo: Baker, Yul (PHMSA)\nCc: Hazmat Interps\nSubject: FW: Letter of Interpretation Request\nDate: Tuesday, June 24, 2025 12:19:31\nAttachments: image001.png\nimage004.png\nHi Yul,\nPlease see the below interpretation request.\nLet us know if you need anything,\n-Breanna\nFrom: Henderson, Dustin <Dustin.Henderson@dps.texas.gov>\nSent: Monday, June 23, 2025 8:47 PM\nTo: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>\nSubject: Letter of Interpretation Request\nCAUTION: This email originated from outside of the Department of Transportation (DOT). Do not click on links or open attachments unless you\nrecognize the sender and know the content is safe.\nMay I get a formal letter of interpretation on the following:\nA frac tank is a large piece of mobile equipment used to store bulk liquids. These tanks get their name from their popularity in the oil & gas industry.\nThey commonly store fluids and diesel fuel on site during oilfield operations. They range in capacity from 8,400 to 210,000 gallons, therefore meeting\nthe bulk package definition. They are typically manufactured with a single or tandem axle and are not designed to transport liquids. Since they are not\n“intended primarily for the carriage of liquids or gases,” they do not meet the definition of a cargo tank. Still, they are often transported with diesel or\ndiesel residue. I’ve attached two photos for reference.\n1. 2. 3. 4. 5. Does a frac tank meet the definition of portable tank in 171.8?\nIf it meets the portable tank definition, is NA1993, Diesel Fuel, 3, PGIII authorized for transport in a frac tank under 173.241(c)?\nCan NA1993, Diesel Fuel, 3, PGIII be transported in a frac tank as residue?\nCan NA1993, Diesel Fuel, 3, PGIII be transported in a frac tank, while the frac tank is located on a trailer?\nWould the frac tank qualify as a tank and therefore the driver be required a tank endorsement?\n\n<<<PAGE 4>>>\n\n1993\nAGON\nDI\n\n<<<PAGE 5>>>\n\nDustin Henderson, CVE-Corporal IV\nRadiation/Nuclear Threat Detection Unit\n1600 West Loop 306\nSan Angelo, Texas 76904\n432-553-4188-cell","truncated":false,"body_characters":5399}