HazMat Resources, Inc. — Hazardous Materials Safety Interpretation

Page 10 U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 JUL 1 2 2018 Mr. Danny Shelton President HazMat Resources, Inc. 124 Rainbow Drive, Suite 24 71 Livingston, TX 77399-1024 Reference No. 17-0122 Dear Mr. Shelton: This letter is in response to your November 1, 2017, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the marking and inspection of U.S. Department of Transportation specification cargo tank motor vehicles (CTMV). We have paraphrased and answered your questions as follows: Q 1. You ask if the manufactured thickness must be marked on a nameplate when the manufacturer builds in a corrosion allowance. Al. The answer is yes. As prescribed in§ 178.345-14(b)(13) and (14), the manufactured thickness is required to be marked on a CTMV nameplate when additional thickness is provided by the manufacturer for corrosion allowance. Q2. You note that a CTMV is not required to have a vacuum breaker if its tank is designed to be loaded by vacuum or built to withstand a full vacuum. Therefore, you ask how a registered inspector is to determine if the CTMV meets the specification requirement if there is no indication on the nameplate that its tank is designed to be loaded by vacuum or built to withstand a full vacuum.#

Page 2A2. Section § 178.345-14(b) of the HMR prescribes the information required to be marked on a cargo tank's nameplate, in addition to any applicable information required by the ASME Code. Paragraph UG-116(a)(4) in Section VIII of the 2015 ASME Code requires the maximum allowable working pressure (MA WP) to be marked on the nameplate as "maximum allowable working pressure (internal or external)," when specified as a design condition. Consequently, if the marked MA WP ( external) is below 1 atmosphere (14. 7 psi), it does not meet the exemption requirements of § 178 .34 7-4(b) and vacuum relief devices (e.g., breaker) are required. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, A-C. \ Shane C. Kelley Director, Standards and Rulemaking Division Office of Hazardous Materials Standards#

Page 3January, lkeya CTR (PHMSA) From: Sent: To: Subject: Foster, Glenn (PHMSA) Monday, November 06, 2017 12:26 PM Dodd, Alice (PHMSA); January, Ikeya CTR (PHMSA) Issues with Specification Plates 11- O(d-J.- Alice/ lkeya, Please have the following inquiry checked in as a request for a Letter of Interpretation and assign it to a Specialist. Thanks, Glenn From: Daniel Shelton [mailto:dshelton@hazmatresources.com] Sent: Wednesday, November 01, 2017 10:39 AM To: Foster, Glenn (PHMSA) <Glenn.Foster@dot.gov> Cc: Bomgardner, Paul (FMCSA) <paul.bomgardner@dot.gov>; Fleener, Arthur (FMCSA) <arthur.fleener@dot.gov>; Ellis, Suzanne (FMCSA) <Suzanne.Ellis@dot.gov>; Ford, David (FMCSA) <david.ford@dot.gov>; Simmons, James (FMCSA) <james.simmons@dot.gov>; Solomey, Joe (OST) <Joe.Solomey@dot.gov> Subject: Issues with Specification Plates Good morning Mr. Foster, When a DOT 407 stainless steel cargo tank is manufacturer, it is my understanding that the manufactured thickness is required to be on the specification plate so one can calculate the corrosion allowance when performing a thickness test. Question: Is the manufactured thickness required to stamped on the specification plate for a cargo tank when the manufacture builds in a corrosion allowance. It is my understand that a DOT 407 is not required to have a vacuum breaker if the tanks is "designed to be loaded by vacuum" or "built to withstand full vacuum". How does a registered inspector determine if the cargo tank meets the specification requirement when there is no indication on the specification plate that the cargo tank is "designed to be loaded by vacuum" or "built to withstand full vacuum"? Question: How does the registered inspector determine whether or not a vacuum breaker is required on a DOT 407 cargo tank. Regards Glenn, can you please confirmed that you received this message 1#