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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #03-0198 ([Heritage Environmental Services] [Mr. David E. Blair])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Heritage Environmental Services

Individual Name: Mr. David E. Blair

Location State: WA Country: US

View the Interpretation Document

Response text:

Dec 3, 2003


Mr. David E. Blair                             Ref No: 03-0198

Heritage Environmental Services

9370-E1 Lathrop Industrial Drive

Olympia, Washington 98512

Dear Mr. Blair:

This is in response to your August 7, 2003 e-mail requesting clarification on the segregation requirements under § 177 .848( e)(1) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180)for Division 2.3, Zone A and Zone B poisonous gases. Specifically, you ask if the absence of any hazard class or division or a blank space in the segregation table indicates that no restrictions apply to the loading, transportation, or storage of these materials.

You ask if the HMR imposes any segregation restrictions on the transportation of the following materials shipped on the same transport vehicle:

  • Phosphine " Division 2.3, Zone A
  • Hydrogen Sulfide " Division 2.3, ZoneB
  • Germane - Division 2.3, ZoneB
  • Nitric Oxide " Division 2.3, Zone A
  • Phosgene " Division 2.3, Zone A
  • Stibine " Division 2.3; Zone A
  • Tungsten Hexafluoride " Division 2.3, Zone A
  • Phosphorus Pentafluoride, compressed " Division 2.3, Zone B

Instructions for use of the § 177.848 Segregation Table state that "the absence of any hazard class or division or a blank space in the Table indicates that no restrictions apply" (§ 178.848(e)(1)). In addition, § 177. 848( e)( 6) states that segregation appropriate to the subsidiary hazard must be applied when that segregation is more restrictive than that required by the primary hazard. However,§ 177.848(e)(6) allows materials of the same hazard class to be transported together without regard to segregation required for any secondary hazard if the materials are not capable of reacting dangerously with each other and causing combustion or dangerous evolution of heat; evolution of flammable, poisonous or asphyxiant gases; or formation of corrosive or unstable materials. Therefore, since the

materials listed above are of the same hazard class (Division 2.3), and not otherwise incompatible, they may be shipped on the same transport vehicle.

I hope this satisfies your inquiry. If you need additional assistance, do not hesitate to contact us.



Susan Gorsky

Senior Transportation Regulations Specialist

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
177.848 Segregation of hazardous materials