# Technology and Management Systems, Inc. — Hazardous Materials Safety Interpretation **Citation:** 00-0278 **Type / status:** guidance / guidance **Agency:** Pipeline and Hazardous Materials Safety Administration **Effective:** Not stated **Published:** 2001-02-02 00-0278 response to Technology and Management Systems, Inc. concerning 179.13, 179.22. ## Document text <<>> U.S. Department 400 Seventh Street. S.W. of Transportation Washington, D.C. 20590 FEB - 2 2001 Mr. Phani Raj Ref. No. 00-0278 President Technology and Management Systems, Inc. Suite 210 99 South Bedford Street Burlington, Massachusetts 01803 Dear Mr. Raj: This responds to your letter, dated September 27, 2000, concerning provisions in the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the rail transportation of hazardous materials. Your specific questions are paraphrased and answered below. Q1. The table in § 171.7 lists material incorporated by reference into the HMR. Do all materials in the referenced sources become HIMR requirements or only those sections of the referenced sources specifically identified in sections of the HMR? A1. The standards and other material listed as matter incorporated by reference in § 171.7 are incorporated into the HMR in their entirety. If only a part of an industry or international standard is incorporated into the HMR, the table entry specifies the section or sections of the standard. Thus, the table lists the separate sections of the Association of American Railroads (AAR) Manual of Standards and Recommended Practices that are incorporated by reference in the HMR. Sections not specifically listed are not incorporated by reference. Q2. If the HMR refer to particular requirements in a referenced source and the referenced source further references a secondary source, do the pertinent sections of the secondary source automatically become part of the HMR requirements? A2. No. Material specifically listed in the table in § 171.7 is incorporated by reference into the HMR. However, secondary sources referred to in the incorporated reference, such as the ASME Code, ASTM Standards, or the AAR Standards, are not thereby incorporated by reference. (Note that such secondary sources may separately and directly be incorporated by reference elsewhere in the HMR.) In the example you provide in your letter, Rule 70 of the AAR Field Manual is referenced in Appendix C of the Tank Car HMR. 000278 <<>> Q3. What is the purpose of the requirement in § 179.22 that all tank cars be stenciled? May a tank car be loaded with a hazardous material in an amount that exceeds the amount specified on a stencil so long as the HMR provisions concerning outage and filling limits are met? A3. Section 179.22 requires tank cars to be "marked" according to the requirements in Appendix C of the AAR Specifications for tank cars. A marking is a descriptive name, identification number, instructions, cautions, weight, specification, or UN marks, or a ombination thereof required by the HMR. The purpose of referencing Appendix C o he AAR Tank Car Manual is to ensure that all markings required by the HMR are place in a location on the tank that is consistent with all other tank cars in transport. Having markings in the same location on each tank car makes consistent the identification of the tank by railroad and emergency response personnel alike. stamping. Marking requirements depend on the applicable tank car specification. For tank cars, marking is accomplished by stenciling (applied with paint or decal) and Generally, a tank car must be stamped on both outside heads with the specification number to which the tank was built, which must also include the material of construction, cladding material (if any used), tank builder's initials, date of original test, car assemblers initials (if other than tank builder), and water capacity. In addition, a tank car must be stenciled on its side with the tank car specification number, water capacity, test dates, reporting mark, load limit, and other information relevant to the particular specification or the commodity to be transported. Tank car outage and filling limits for specific commodities are addressed in several different places in the HMR. For example, § 173.24b(a) prescribes general outage and filling limits for liquids and liquefied gases. In addition, § 173.314 specifies outage and filling limits for compressed gases in tank cars. Section 173.24b(d)(2) states that, unless otherwise provided in the HMR, a tank car may not be loaded with a hazardous material that exceeds the maximum weight of lading marked on the specification plate. For a tank car, the "specification plate" means the information stamped on its outside heads. This marking does not include load limits, because that is generally a function of the carrying capacity of the underframe, trucks, and axle loadings. Thus, federal rules prohibit new construction of cars having a gross weight on rail that exceeds 263,000 pounds or greater than 34,500 gallon capacity. The regulations also prohibit the loading of product into a tank that exceeds the outage requirements in 173.24b and 173.314. 'The HMR do not currently specify load limits for tank cars. Q4. Should the words "specification plate" as used in § 173.24b(d)(2), be interpreted as the word "stencil" when applying this section to tank cars? A4. As stated above, the term specification plate means the stamping located on each tank car head. <<>> • Q5. Is it correct that § 179.13 addresses limitations on a tank car's maximum size (by weight or capacity) rather than the maximum allowable load limit (as indicated by its stencil marking)? AS. Your understanding is correct. Section 179.13 sets the upper limit for the maximum capacity and weight of any tank car built or converted after November 30, 1970. The load limit of a tank car is the difference between the maximum permissible gross weight on rail (based on the axle size) and the lightweight of the car. In addition, cars may not be overloaded by volume (See § 173.24b) I hope this information is helpful. If you have any questions, please do not hesitate to contact this office. Sincerely, one All Thomas G. Allan Transportation Regulations Specialist Office of Hazardous Materials Standards <<>> Gorsku 110.13 179.22 September 27, 2000 Marking t TMS Research & Special Programs Administration Office of Hazardous Materiale Standards (DHM-10) WejahtLim, tation Inc. U.S. Department of Transportation 400 Seventh Street, S.W. WASHINGTON, DC 20590-0001 REFERENCE: Formal Interpretation of Hazardous Materials Regulations SUBJECT: Request for formal clarifications on certain HMR Provisions Gentlemen: Pursuant to the provisions of 49CFR §107.14, I request your formal response to the following questions related to the transportation of hazardous materials on rail. The table in 49CFR §170.7 indicates a number of referenced sources. Should one construe the provisions/requirements/specifications in these referenced materials as being a part of the provisions/requirements/specifications of the 49CFR? Do all materials in the referenced sources become requirements of 49CFR or only those sections of the referenced sources specifically identified in the 49CFR sections become formal requirements? 2 If a 49CFR section refers to particular requirements in a referenced source and the referenced source further references a secondary source, do the pertinent sections of the secondary source become automatically a part of the 49CFR requirements? Let me give an example to highlight this issue. 49CFR $179.22 (a) (October 1, 1998 version) on "Marking" requires that "Each tank car must be marked according to the requirements in Appendix Cof AAR Specification for Tank Cars." Section C7.00 "Load Limit Stencil", subsection (d) of Appendix C of Tank Car Specifications indicates that "Load limit is the difference between the total weight on rail for the journal size and the scale light weight of the car. See Field manual Rule 70.B.3.b." hazardous material and with a gross weight exceeding the maximum permissible weight specified (for the particular journal size) in Rule 70 (or for that matter in Rule 91) of the Technology & Management Systems, Inc. 99 South Bedford Street, Suite 210 + Burlington, MA 01803-5153 + Tel 781-272-3033 + Fax 781-272-5038 • E-Mail: tmsinc@tiac.net + Page 1 of 2 <<>> • 3 What is the regulatory purpose of requiring that all tank cars be "Stenciled?" (49CFR §179.22 in the October 1, 1998 version and §179-100.21 in versions earlier than 1996). How are the specification on a stencil enforced by US DOT? There does not seem to be any requirement prohibiting the carrying of a hazardous material in a tank car in excess of the amount (weight or volume) specified on the stencil so long as the provisions of 49CFR §173.24b (a) "outage and filling limits" are complied with. Please clarify the HM regulations regarding the enforcement of stenciled amounts. 4 material that exceeds the maximum weight of the lading marked on the specification plate." 49CFR §$173.24b (d) (2) states "A bulk packaging may not be loaded with a hazardous In the case of the tank car since there is no "specification plate" and stencil is the medium that "specifies" the lading weight, do the provisions of this subsection apply to a tank car? Should the words "specification plate" be interpreted as the word "stencil" when the applicability of this subsection to a tank car is being evaluated? Please note that §173.24b (a) clearly applies to a tank car. 5 My interpretation of the provisions in 49CFR §179.13 "Tank car capacity and gross weight I look forward to receiving your formal interpretation to the above questions at the earliest possible time. Yours truly, PRomi Ray President Technology & Management Systems, Inc. 99 South Bedford Street, Suite 210 + Burlington, MA 01803-5153 + Tel 781-272-3033 + Fax 781-272-5038 • E-Mail: tmsinc@tiac.net+ Page 2 of 2 ## Provenance - Official: Yes - Source: - Source ID: `phmsa` - SHA-256: `d94ab49797ee2ccbd54640cd8c5f7f1e73f809c970cc13604099bbb2ba3f7269` - Retrieved: 2026-08-20T00:59:31.977Z - Exported: 2026-08-22T21:55:07.547Z - Document slug: `phmsa-interpretation-00-0278` ### Source metadata ```json { "materialSubtype": "interpretation", "interpretationArea": "hazardous_materials", "representation": "full_text_from_official_pdf", "companies": [ "Technology and Management Systems, Inc." ], "individuals": [ "Mr. Phani Rai" ], "refIds": [ "00-0278" ], "catalogDates": [ "2001-02-02" ], "catalogParts": [ 179 ], "catalogRowCount": 2, "sourceRecordUrls": [ "https://www.phmsa.dot.gov/node/60196" ], "linkedAttachmentUrls": [], "unavailableResponseUrls": [], "duplicateRepresentationUrls": [], "citedSections": [ "179.13", "179.22", "171.7", "173.24b(a)", "173.314", "107.14" ], "catalogPageUrls": [ "https://www.phmsa.dot.gov/regulations/title49/section/17913", "https://www.phmsa.dot.gov/regulations/title49/section/17922" ], "pdfUrls": [ "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/2000/000278.pdf" ], "representations": [ { "viewUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/2000/000278.pdf", "detailUrl": null, "detailHtmlPath": null, "pdfUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/2000/000278.pdf", "pdfArtifactPath": "data/sources/phmsa-interpretations/00-0278-a11ec418b6.pdf", "pdfArtifactSha256": "97a311c3fe84eb92b64fb1895270a16dce9f1f14eb619e713372bb1ec9ac7ed3", "extractedTextPath": "data/sources/phmsa-interpretations/00-0278-a11ec418b6.v2.txt", "extractedTextSha256": "51d0ded1ae6603a36dbe05bee8495835fda6a0b4d99b308612bf1730a5ce306c", "pageCount": 5, "extractionVersion": 2 } ], "caveat": "Interpretations apply regulations to the facts presented and do not create independently enforceable requirements.", "jurisdiction": "US" } ```