{"operation":"document","citation":"06-0032","title":"Mr. Thomas Richichi — Hazardous Materials Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"2006-03-24","effective_on":null,"summary":"06-0032 concerning 173.133.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-06-0032.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-06-0032.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-06-0032","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/2006/060032.pdf","body":"<<<PAGE 1>>>\n\nU.S. Department\nof Transportation\n400 Seventh Street, S.W.\nWashington, D.C. 20590\nPipeline and\nHazardous Materials Safety\nAdministration\nMAR 2 4\n200S\nMr. Thomas Richichi\nRef. No.: 06-0032\n1350 I Street, N.W.\nSuite 700\nWashington, D.C. 20005\nMr. Richichi:\nThis is in response to your letter regarding the assignment of packing group and hazard\nzones for Division 6.1 materials under § 173.133(a) of the Hazardous Materials Regulations\n(HMR; 49 CFR Parts 171-180). You reference a January 29, 1997 letter of interpretation\nfrom Delmer F. Billings to James R. Barrett in which we indicated that a material with a low\nvapor pressure such that it cannot readily vaporize or mist in transportation is not required to\nbe evaluated against the inhalation exposure criteria in § 173.133(b). Specifically, you\nrequest confirmation that the letter applies to the packing group and hazard zone assignment\ncriteria in § 173.133(b) and the criteria in § 173.133(a).\nThe January 29, 1997 letter you reference provides general classification procedures (i.e.,\ndetermination of hazard class, hazard zone, packing group for Division 6.1 materials.\nTherefore, the letter applies to all of §§ 173.132 and 173.133, as applicable, including the\npacking group and hazard zone criteria in paragraphs (a) and (b) of § 173.133.\nI hope this information is helpful. Please contact us if you require additional assistance.\nSincerely,\nChief, Standards Development\nOffice of Hazardous Materials Standards\n173.133 (a)\n060032\n\n<<<PAGE 2>>>\n\nSupko\nBEVERIDGE\n5173.133(0)\n& DIAMONDpC\nlacking -0052\n1350 | Street, N.W.\nThomas Kichichi\nWashington. D.C. 20005-3311\nSuite 7CO\nDirect: (202) 789-6026\ntrichichi@bdion.com\nFax: (202) 789-6190\nFebruary 3, 2006\nMr. Edward T. Mazzullo\nDirector, Office of Hazardous Materials Standards\nUS DOT/PHMSA (DHM-10)\n400 7th Street, S.W.\nWashington, D.C. 20590-0001\nRe: Packing Group and Hazard Zone Assignment Based on Inhalation Toxicity\nDear Mr. Mazzullo:\nWe have been asked to inquire about the applicability of certain inhalation toxicity\nand guidance regarding a determination of whether inhalation toxicity must be considered ir\ncriteria to the transportation of a chemical substance. In particular, 1 write to request clarification\ndeeming 40 C.c.R. Par u73, proard on of Depart undo thranspordius aDi\", and\nspecifically 49 C.F.R. § 173.133(a) which provides criteria for determining the packing group\nand hazard zone assignments for Division 6.1 materials.\nnot have to be considered in determinations of whether a material is a Division 6.1 poison if that\nIt is our understanding that DOT has previously determined that inhalation toxicity does\nmaterial will not readily form a vapor or mist \"under conditions normally incident to\ntransportation.\" See attached Letter from Delmer F. Billings, DOT, to James R. Barrett, Latham\n& Watkins (January 29, 1997) (\"1997 DOT Letter\"), responding to the Letter from James R.\nBarrett, Latham & Watkins, to Delmer F. Billings, DOT (August 2, 1996) (\"Barrett Letter\"). We\nwould like confirmation that the analysis in the 1997 DOT Letter not only applies when\ndetermining whether a material is a Division 6.1 poisonous material, but also applies to\nassignments of packing group and hazard zone under 49 C.F.R. § 173.133(a).\nSpecifically, the regulations provide for assignment of packing group based on criteria\nfor oral, dermal, and inhalation toxicity by dusts and mists. See 49 C.F.R. § 173.133(a)(1). The\n1997 DOT Letter concluded that inhalation toxicity need not be considered in classifying a\nmaterial as a Division 6.1 poisonous material if it did not readily form a mist under conditions\nnormally incident to transportation. The material that was the subject of the 1997 DOT letter\nWashington, D.C. Maryland\nNew York Massachusetts\nNew Jersey\nTexas California\n\n<<<PAGE 3>>>\n\nBEVERIDGE & DIAMOND c\nEdward T. Mazzullo\nFebruary 3, 2006\nPage 2\ncould, however, form an aerosol when subjected to mechanical manipulation. Barrett Letter at 2.\nWe would like to confirm the conclusion suggested by the 1997 letter that inhalation toxicity by\ndusts and mists need not be considered when assigning a packing group to a substance that does\nnot readily form a dust or mist under conditions normally incident to transportation, even though\nit might be possible to form an aerosol if the substance were subjected to mechanical\nmanipulation as described in the Barrett Letter.\nRelated to this, the regulations also provide for assignment of packing group and hazard\nzone based on criteria for volatility and inhalation toxicity for vapors. See 49 C.F.R.\n§ 173.133(a)(2). Again, the 1997 DOT Letter concluded that inhalation toxicity need not be\nconsidered in classifying a material as a Division 6.1 poisonous material, if it did not readily\nform a vapor under conditions normally incident to transportation. The material that was the\nsubject of the 1997 DOT letter had a vapor pressure in the range of 104 mm Hg. Barrett Letter\nat 2. We would also like to confirm that inhalation toxicity by vapors need not be considered\nwhen determining packing group and hazard zone if the substance does not readily form a vapor\nunder conditions normally incident to transportation and the substance's low vapor pressure\n(eg., in the range of 104 mm Hg) effectively precludes performance of an acute inhalation study\non the substance as a vapor under such conditions.\nThank you for your attention to this matter. Please feel free to contact me if you have\nany questions or if you need additional information to respond to this request.\nSincerely yours,\n(Imm Ridice.\nThomas Richichi\nAttachments","truncated":false,"body_characters":5626}