Mr. Kent Blair — Hazardous Materials Safety Interpretation

Page 1of Transportation U.S. Department 400 Seventh Street, S.W. Research and Washington, D.C. 20590 Special Programs Administration APR 1 7 1998 Mr. Kent Blair 24489 Mullin Road Dexter, NY 13634 Dear Mr. Blair: This is in response to your letter dated February 2, 1998, requesting clarification on the transportation of explosives on vehicles in combination. Specifically you ask whether Division 1.1 or 1.2 explosives may be carried on any vehicle or combination of vehicles with any Division 2.3 (poison gas) or 6.1 (poisonous) materials under the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180). The answer is no. Section 177.835(c) states that Division 1.1 or 1.2 materials may not be loaded into or carried on any vehicle or a combination of vehicles if the other vehicle in the combination contains "Division 2.3 (poisonous gas) or Division 6.1 (poisonous ) materials." The phrase "Division 2.3 (poisonous gas) or Division 6.1 (poisonous ) materials" includes all Division 2.3 materials, regardless of hazard zone, and all Division 6.1 material, regardless of the physical state or packing group of the material. I hope this satisfies your request. Sincerely, Delmer F. Billings Chief, Standards Development Office of Hazardous Materials Standards#

Page 2Sale 7= Til 424, 35, 17848 Kent F. Blair 24489 Mullin Road Dexter, NY 13634 February 4, 1998 Edward Mazzullo Director Office of Hazardous Materials Stds. - 400 7th Street Southwest Washington, D.C. 20590 RE: Request for clarification 49 CFR 177.835 (c) (4) (iii) Dear Mr. Mazzullo: The undersigned's interpretation of the regulatory guidance contained 49 CFR 177.835 (C) (4) (iii), conflicts with the regulatory guidance contained within 49 CFR 177.848, Segregation Table For Hazardous Materials, specifically: The undersigned interprets the regulatory guidance contained within 49 CFR 177.835 (C) (4) (111) as prohibiting DIViSIOn 1.1 O 1.2 (explosive) materials from being loaded into or carried on any vehicle of a combination of vehicles if the other vehicle in the combination contains any material. Division 2.3 (poisonous gas) or Division 6.1 (poisonous) The term "any" is interpreted to be all inclusive, meaning any Division 2.3 (poisonous gas), any Division 6.1 (poisonous) material, irrespective of hazard zone, physical state (e.g. liquid) and/or packaging group assigned. Within 49 CFR 177.848, Segregation Table For Hazardous Materials, the listings applicable to Division 2.3 (poisonous gas) and Division 6.1 (poisonous) material is not all inclusive. Only Poisonous gas Zone A, Poisonous gas Zone B, and Poisonous Liquids PG I, Zone A, are considered for the purpose of segregation during loading, storage or transport.#

Page 3Edward Mazzullo Director Office of Hazardous Materials Stds. 400 7th Street Southwest Washington, D.C. 20590 RE: Request for clarification 49 CFR 177.835 (c) (4) (iii) Page 2 of 2 clarification applicable to the following. Due to the perceived conflict, respectfully request 1. With respect to 49 CFR 177.835 (c) (4) (iii), is the intent to prohibit any Division 2.3 (poisonous gas) or Division 6.1 (poisonous) material, irrespective of hazard zone, physical state (e.g. liquid) and/or packaging group assigned, from being loaded into or carried on any vehicle of a combination of vehicles if the other vehicle in the material ? combination contains any Division 1.1, 1.2 (explosive) 2. If not, what specific Division 2.3 (poisonous gas) or 6.1 (poisonous) material, (respective of hazard zone, physical state (e.g. liquid) and/or packaging group assigned) is prohibited from being loaded into or carried on any vehicle of a combination of vehicles if the other vehicle in the combination contains any Division 1.1, 1.2 (explosive) material ? Sincerely, Kent F. Blair#