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Interpretation Response #11-0242 ([Dynax Corporation] [Chang Jho, Ph.D. Dynax Corporation])

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

Interpretation Response Details

Response Publish Date:

Company Name: Dynax Corporation

Individual Name: Chang Jho, Ph.D. Dynax Corporation

Location State: NY Country: US

View the Interpretation Document

Response text:

November 15, 2011



Chang Jho, Ph.D.

Dynax Corporation

79 Westchester Ave.

PO Box 285

Pound Ridge, NY 10576

Reference No. 11-0242

Dear Dr. Jho:

This is in response to your September 26, 2011 e-mail to Charles Ke, Ph.D., Chemist, Sciences Branch, Engineering and Research Division, Pipeline and Hazardous Materials Safety Administration (PHMSA). Dr. Ke forwarded your e-mail to PHMSA"s Standards and Rulemaking Division for reply. Specifically, you ask if a concentrated surfactant solution that has a flash point of 27 ºC and a boiling point greater 100 ºC but does not sustain combustibility, is excepted from regulation as a flammable liquid under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

You state your product, DX2200, contains solids (40 percent), water, and some tert-Butyl alcohol, which is described as "UN 1120, Butanols, 3, PG II or III" in the HMR"s Hazardous Materials Table (§ 172.101). You also enclosed a copy of a September 20, 2011 "Sustained Combustibility Testing" laboratory report, No. 11212, prepared by Stresau Laboratory, Inc., which concludes that the sample it tested "did not appear to sustain combustion at either the 60.5 ºC or the 75.0 ºC temperatures tested, which were raised to temperatures corresponding to actual barometric pressures at test initiations in order to compensate for the lower than standard barometric pressures as required by" the required testing criteria. It also describes these tests as being in compliance with the requirements of the HMR and United Nations Transport of Dangerous Goods Manual of Tests and Criteria, fifth revised edition (2009), Test Method L.2.

Under the HMR, a material that is a liquid with a flash point of not more than 60 ºC (140 ºF) meets the definition of a flammable liquid (see § 173.120(a)). However, if experience or other data indicates that the hazard of flammable liquid or combustible liquid material is greater or less than indicated by the criteria specified in § 173.120(a) or (b), the Associate Administrator of Hazardous Materials Safety may revise the classification or make the material subject or not subject to the requirements of 49 CFR Parts 170-189 (see

§ 173.120(d)). After reviewing the test data and analysis submitted with your request, we agree that the "concentrated surfactant solution" you described may be excepted from regulation under the HMR, under the provisions of § 173.120(d), as a Class 3 (flammable liquid) material.

I hope this satisfies your request.


T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division


Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.120 Class 3-Definitions