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Interpretation Response #08-0050 ([Bell, Boyd & Lloyd, LLP] [Mr. Thomas R. Carey])

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

Interpretation Response Details

Response Publish Date:

Company Name: Bell, Boyd & Lloyd, LLP

Individual Name: Mr. Thomas R. Carey

Location State: IL Country: US

View the Interpretation Document

Response text:

July 2, 2008

Mr. Thomas R. Carey

Bell, Boyd & Lloyd, LLP

70 W. Madison St.

Suite 3100

Chicago, IL 60602

Ref. No. 08-0050

Dear Mr. Carey:

This is in response to your August 29, 2007 request for clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the hazard class and transportation by highway and rail of forbidden materials that are stabilized or diluted. I apologize for our delay in responding and any inconvenience this may have caused.

In your letter, you state that the company you represent, CDG Research Corporation, has manufactured a proprietary 0.3% (i.e., 3,000 parts-per-million) chlorine dioxide aqueous solution named "CDG Solution 3000." This product is manufactured from a material forbidden for transportation under the HMR, pure chlorine dioxide, but has been diluted more than 300:1 (99.7%) with water and is stabilized. In your letter, you also state that: (1) test data show that CDG Solution 3000, at full strength, exhibits corrosion on steel and aluminum surfaces exceeding 6.25 mm (0.25 inch) a year at a test temperature of 55 °C (130 °F); (2) test data show that this material does not cause full thickness destruction of intact skin tissue within an observation period of up to 14 days starting after the exposure time of more than 60 minutes but not more than 4 hours; and (3) the product is not an organic peroxide, explosive, or self-reactive material as defined by the HMR, and is not listed as a marine pollutant. You ask whether: (1) this product is subject to the prohibition of "Chlorine dioxide (not hydrate)" under the HMR; (2) there are requirements for formal DOT approval or authorization prior to surface transportation by highway or rail; and (3) if this product should be classed as a "corrosive" material (Class 8) with a Packing Group of III.

As specified in § 172.101(d)(1), if any specifically listed, pure, forbidden material is stabilized or diluted or incorporated in a device and is classed in accordance with the definitions of hazardous materials contained in Part 173 of the HMR, it is no longer considered a forbidden material. It is your responsibility to ensure the material is stabilized, classed, and transported in accordance with the HMR. Organic peroxides, explosives, and self-reactive materials require formal approval from the Associate Administrator for Hazardous Materials Safety. For other than these materials, no formal approval or authorization is required from DOT to dilute, stabilize, and transport the material. In addition, the proper shipping name "Chlorine dioxide (not hydrate)" does not apply to the diluted and stabilized material as described in your letter. Your product appears to meet the definition of a corrosive material (Class 8), Packing Group III. Therefore, a more appropriate proper shipping description is "Corrosive liquid n.o.s., (0.3% Chlorine dioxide), 8, UN1760, PG III. If you believe the diluted condition of 3000 ppm is stabilized, an appropriate proper shipping description is "Corrosive liquid n.o.s., (0.3% Chlorine dioxide, stabilized), 8, UN1760, PG III.

I hope this information is helpful.


Susan Gorsky,

Regulations Officer

Office of Hazardous Materials Standards

172.101 171.8 173.21

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table