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Interpretation Response #09-0144 ([Cytec Industries Stamford Hazards Lab] [Mr. Mark Ryan])

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

Interpretation Response Details

Response Publish Date:

Company Name: Cytec Industries Stamford Hazards Lab

Individual Name: Mr. Mark Ryan

Location State: CT Country: US

View the Interpretation Document

Response text:

July 31, 2009




Mr. Mark Ryan

Cytec Industries

Stamford Hazards Lab

1937 W Main St

Stamford, CT 06902-4516

Ref. No. 09-0144

Dear Mr. Ryan:

This responds to your June 19, 2009 letter requesting clarification on whether the attached ARC test method may be used to determine a material"s self-accelerated decomposition temperature (SADT) under §173.21(f) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171"180). Specifically, you ask if a test method, other than those listed in Part II, Section 28, test series H of the UN Manual of Tests and Criteria, may be used to meet the requirements of § 173.21(f) of the HMR.

The answer is yes. Section 173.21(f) specifies the SADT may be determined by any of the test methods described in Part II, of the UN Manual of Tests and Criteria. These UN provisions, in 28.2.2, also provide that test methods, other than those listed, are authorized provided the alternative method gives the correct SADT of the material as packaged for transport.

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
173.21 Forbidden materials and packages