Stabilis Solutions — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 May 28, 2021 Mr. Vignesh Pandurengan Maintenance Specialist Stabilis Solutions 10375 Richmond Avenue, Suite 700 Houston, TX 77042 Reference No. 20-0094 Dear Mr. Pandurengan: This is in response to your December 7, 2020, email and subsequent conversations with a member of my staff requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to Department of Transportation (DOT) cargo tanks. Specifically, you ask whether an insulated MC 338 cargo tank transporting non-corrosive materials and equipped with manholes must undergo an internal visual inspection within certain time intervals. Section 180.407(c) excepts DOT Specification MC 338 cargo tanks from the internal visual inspection requirement when transporting non-corrosive materials. However, MC 338 cargo tanks are required to be externally inspected annually. If the insulation of the MC 338 cargo tank you describe is found to preclude a complete external inspection, an internal inspection of the cargo tank would be required in order to meet the external inspection requirements specified in §§ 180.407(c) and 180.407(d). In addition, because the cargo tank you describe is equipped with manholes, Note 4 of § 180.407(c) would apply, and you may perform either an internal visual inspection in conjunction with the external visual inspection or a hydrostatic or pneumatic pressure-test of the cargo tank. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, T. Glenn Foster Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division#

Page 2Edmonson 20-0094 From: INFOCNTR (PHMSA) To: Subject: Date: Dodd, Alice (PHMSA); Hazmat Interps FW: Request for Letter of Interpretation Monday, December 7, 2020 11:58:24 AM Dear Alice, Please see the request for a letter of interpretation below. Please contact our office with any questions. Thank you, Sarah (HMIC) From: Vignesh Pandurengan [mailto:vpandurengan@stabilis-solutions.com] Sent: Monday, December 7, 2020 8:37 AM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Cc: Miroslaw Skrzypkowski <Mskrzypkowski@stabilis-solutions.com>; Travis Vandervort <tvandervort@stabilis-solutions.com>; Koby Knight <koby.knight@stabilisenergy.com>; Jessica Lopez <jessica.lopez@stabilis-solutions.com>; Crystal Alcalar <crystal.alcalar@stabilis- solutions.com> Subject: Request for Letter of Interpretation 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. To Whom It May Concern, I am writing to request a letter of interpretation of the regulation that defines internal visual inspection requirements of MC338s tanks that have manholes/manways. I spoke with a regulatory specialist, Breanna, who was very thorough and escalated the question of whether or not MC338s tanks that have manholes/manways are required to have internal visual inspections at ANY interval of time to other specialists and to personnel at the PHMSA Standards department. She got back to me and reported that MC338 units with manholes/manways are NOT required by the CFR to have internal inspections but we may do so at our own discretion. The portions of the regulation that define the inspection requirements are 49 CFR 180.407 in the sections shown below:#

Page 3Please provide a formal interpretation letter for our confirmation and review at your earliest convenience, the physical mailing address to which the letter can be sent is in my signature below. Regards, Vignesh Pandurengan#

Page 4Maintenance Specialist Stabilis Solutions 10375 Richmond Avenue, Suite 700 Houston, Texas 77042 Corporate Office Main: 832.456.6500 Toll Free: 1.866.LNG.FUEL Direct: 832.456.6506 Mobile: 281.203.4552 https://www.stabilisenergy.com This message (including any attachments) contains confidential information intended for a specific individual and purpose, and is protected by law. If you are not the intended recipient, you should delete this message and any disclosure, copying, or distribution of this message, or the taking of any action based on it by you is strictly prohibited.#