You are here

Interpretation Response #10-0012

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

Interpretation Response Details

Response Publish Date: 03-01-2010
Company Name: Detector Electronics Corporation    Individual Name: Mr. Jon Varner
Location state: MN    Country: US

View the Interpretation Document

Response text:

March 1, 2010




Mr. Jon Varner
Director of Engineering
Detector Electronics Corporation
6901 West 110th Street
Minneapolis, Minnesota 55438

Ref. No. 10-0012

Dear Mr. Varner:

This responds to your email dated January 12, 2010 requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Your company manufactures a gas detection device designed to detect hydrogen sulfide (H2S). The calibration method for the H2S gas detection device requires the use of glass ampoules containing H2S. Specifically, you ask PHMSA to confirm that based on the LC50 value, the method of packing, and shipment quantities, the H2S ampoules are transported in a form and quantity that does not pose an unreasonable risk to health and safety or property, and therefore are not subject to the HMR.

You provide the following supplemental information:

Each ampoule has a volume of 7 ml and is filled with H2S, which based on your calculations is equivalent to a concentration of 0.49%. You have determined through calculations that the LC50 of the H2S mixture contained in each glass ampoule is 145,510 ml/m3. The ampoules are packed in blocks of foam, 6 ampoules per block. Two foam blocks are packed per corrugated outer box. These boxes are then overpacked in a box with 300 lbs. burst strength with additional packing material, and/or other items. Shipments typically include 100 ampoules and are not anticipated to exceed 1,000 ampoules.

A Division 2.3 (gas poisonous by inhalation) material is defined as a gas that is known to be so toxic to humans as to pose a hazard to health during transportation; or, in the absence of data on human toxicity, is presumed to be toxic to humans because when tested in a laboratory it has an LC50 of 5,000 ml/m3. Based upon the calculated LC50, the material you describe in your letter

does not meet the definition of a Division 2.3 material. Therefore, provided the material does not meet the definition of any other hazard class, it is not subject to the requirements of the HMR.

I hope this answers your inquiry. If you need further assistance, please contact this office at 202-366-8553.


Charles E. Betts
Chief, Standards Development
Office of Hazardous Materials Standards

171.1, 173.132, 172.101, 173.115

Regulation Sections

Section Subject
§ 173.115 Class 2, Divisions 2.1, 2.2, and 2.3-Definitions