# Texas Highway Patrol Division — Hazardous Materials Safety Interpretation **Citation:** 18-0052 **Type / status:** guidance / guidance **Agency:** Pipeline and Hazardous Materials Safety Administration **Effective:** Not stated **Published:** 2018-08-20 18-0052 response to Texas Highway Patrol Division concerning 172.101. ## Document text <<>> Texas Highway Patrol Division Commercial Vehicle Enforcement Training Unit 6200 Guadalupe St., Bldg. P Austin, TX 78752 Reference No. 18-0052 Dear Sergeant Gibson: This letter is in response to your April 2, 2018, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the selection of a proper shipping name. Specifically, you ask whether the optional, italicized text of a proper shipping name shown in the § 172.101 Hazardous Materials Table (HMT) may be modified. In your email, you provide an example of the following description and ask whether the word substance in the optional text may be modified to read material. UN1942, Ammonium nitrate, with not more than 0.2% combustible substances [materials], including any organic substance [material] calculated as carbon, to the exclusion of any other added substance [material] The answer is no. Although the text in italics is not part of the proper shipping name and its use is optional, unless stated otherwise (e.g., actual concentrations in § 172.101(c)(6)), any modification of the shipping description, to include optional text, is not permitted. As prescribed in § 172.101(1(2), any alteration of a shipping description or associated entry which is listed in the § 172.101 HMT must receive prior written approval from the Associate Administrator. 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 <<>> Below is a request for a formal letter of interpretation. Mr. Gibson spoke with Molly. Please let me know if you have any questions. Thank you, Jodi From: brad.gibson dps.texas.gov Sent: Monday, April 02, 2018 3:49 PM To: INFOCNTR (PHMSA) Subject: Request for a Formal Letter of Interpretation Acting Director Kelly, I would like this email to serve as a request for a formal letter of interpretation. I have spoken with multiple NTC certified hazardous materials course instructors, various FMCSA personnel and various PHMSA personnel, including Molly at the Info Center, regarding my question, and cannot obtain a clear answer on an issue concerning the requirements/allowances for a proper shipping description. In short, may the words in italics, that are not part of the proper shipping name, but may be used in addition to the proper shipping name, be modified, such as the interchanging of the word 'material(s)' for the word 'substance(s)'? For example, can someone use either of the following shipping descriptions or are they restricted to the first one listed? • "UN1942, Ammonium nitrate, with not more than 0.2% combustible substances, including any organic substance calculated as carbon, to the exclusion of any other added substance, 5.1, PG III" • "UN1942, Ammonium nitrate, with not more than 0.2% combustible materials, including any organic material calculated as carbon, to the exclusion of any other added material, 5.1, PG III" In the event that word 'material(s)' and the word 'substance(s)' can be interchanged, what other items/words/symbols, not specifically addressed in 172.101(c), may be used interchangeably? I, as well as several others, look forward to your response. Brad Gibson Sergeant, Texas Highway Patrol Division Commercial Vehicle Enforcement Training Unit 6200 Guadalupe St., Bldg. 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