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Interpretation Response #15-0113 ([Evonik Corporation] [Mr. Robert Miller])

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

Interpretation Response Details

Response Publish Date:

Company Name: Evonik Corporation

Individual Name: Mr. Robert Miller

Location State: NJ Country: US

View the Interpretation Document

Response text:

September 30, 2015

Mr. Robert Miller
Manager - Transportation Safety
Evonik Corporation
299 Jefferson Road
Parsippany, NJ 07054

Ref. No. 15-0113

Dear Mr. Miller:

This is in response to your June 11, 2015 e-mail requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the Hazardous Materials Table (HMT) entry "UN1346, silicon powder, amorphous, 4.1, PG III." You state that in both the International Air Transport Association Dangerous Goods Regulations (IATA DGR) and the International Maritime Dangerous Goods (IMDG) Code special provisions A54 and 32, respectively, are assigned to this entry specifying that silicon powder is not regulated as a Division 4.1 flammable solid, and not considered a hazardous material when in forms other than amorphous. You state that an equivalent special provision is not assigned to the entry in the HMR.

You ask if the silicon powder that your company produces, which is in crystalline form, is excepted from the requirements of the HMR for domestic transport without conducting the UN flammability test on the material. In addition you ask if PHMSA intends add an equivalent special provision to the HMR.

The entry "UN1346, silicon powder, amorphous, 4.1, PG III" does not apply to silicon powder in forms other than amorphous. Amorphous silicon is a non-crystalline form of silicon. The UN flammability test is not required to be performed on silicon in crystalline form in order to determine if material meets the criteria for exclusion from Division 4.1.

The HMR do not typically include provisions stating what materials are not regulated. Since non-amorphous silicon powder does not meet the criteria for classification as a Division 4.1 material, it would not be regulated under the HMR. Therefore, at this time there is no intention to add a special provision clarifying that forms other than amorphous are not subject to the requirements of the HMR as the entry is only applicable to silicon when in an amorphous form.

I trust this information is helpful. If you have further questions, please do not hesitate to contact this office.

Sincerely,

 

Duane A. Pfund
International Standards Coordinator
Standards and Rulemaking Division

Regulation Sections