USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

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

Interpretation Response #03-0091 ([NRS America Inc.] [Mr. Domenico Masi])

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

Interpretation Response Details

Response Publish Date:

Company Name: NRS America Inc.

Individual Name: Mr. Domenico Masi

Location State: NY Country: US

View the Interpretation Document

Response text:

Aug 5, 2003


Mr. Domenico Masi                Ref. No. 03-0091
NRS America Inc.
Suite 110
10 Bank Street
White Plains, NY 10606

Dear Mr. Masi:

This responds to your letter requesting clarification of the segregation requirements under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) and the International Maritime Dangerous Goods Code (IMDG Code). Specifically, you inquire whether Dichlorosilane, Division 2.3, UN2189, may be loaded with other Division 2.1 materials in the aame freight container. You state that because dichlorosilane has secondary risks of Division 2.1 and Class 8, the container is rejected based on the general segregation tables in § 176.83 of the HMR and of the IMDG Code requiring Class 8 materials be stowed "away from" Division 2.1 materials.

Under both the dichlorosilane 2.1 materials. dichlorosilane under both the HMR and the IMDG Code, it is permissible to stow in the same freight container with other Division The Class 8 secondary hazard assigned to
is not considered for the purpose of segregation HMR and the IMDG Code.

In the HMR, the specific segregation requirements specified in column (lOB) of the § 172.101 Hazardous Materials Table for dichlorosilane is stowage code "17." Code 17, as set forth in § 176.84, states "segregation same as for flammable gases but "away from" dangerous when wet." Although § 176.83(a) (6) of the HMR requires that all secondary labels be taken into account when determining segregation, paragraph (a) (10) of that section states "where a code in column (lOB) of the § 172.101 Hazardous Materials Table specifies that "segregation as for ... " applies, the segregation requirements applicable to that class in the § 176.83(b) General Table must be applied." (Emphasis added) Therefore, for segregation purposes, dichlorosilane is treated solely as a Division 2.1 material.

Paragraph of the IMDG Code states the segregation provisions for materials having more than two hazards are given in the Dangerous Goods List (DGL). For dichlorosilane, column 16 of the DGL states "segregation as for class 2.1 but ”away from"
class 4.3." Furthermore, paragraph states that the DGL, in the case of conflicting provisions, takes precedence over the general provisions contained in the segregation table. Therefore, again, dichlorosilane is treated solely as a class 2.1 material.

I trust this satisfies your inquiry. Please contact us if we can be of further assistance.



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards

Regulation Sections

Section Subject
171.12 North American Shipments
176.83 Segregation