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Interpretation Response #05-0081 ([Chemical Accident Reconstruction Service, Inc.] [Mr. Michael Fox])

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

Interpretation Response Details

Response Publish Date:

Company Name: Chemical Accident Reconstruction Service, Inc.

Individual Name: Mr. Michael Fox

Location State: AZ Country: US

View the Interpretation Document

Response text:

Jul28, 2005


Mr. Michael Fox                         Reference No. 05-0081
Chemical Accident Reconstruction Service, Inc.
9121 E. Tanque Verde Road #105
Tucson, Arizona 85749

Dear Mr. Fox:

This responds to your March 30, 2005 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to DOT 2Q inner non-refillable metal receptacles. Specifically, you ask if a DOT 2Q container that passes a hydraulic pressure test and fails when subjected to a heat-to-burst test would satisfy the pressure test requirements for DOT 2Q containers specified in § 178.33a-8.

As specified in § 178.33a-8, one out of each lot of 25,000 DOT 2Q containers or fewer, successfully produced each day must be pressure tested to destruction and must not burst below 270 psig. The HMR do not specify the type of pressure test that must be used, nor (10 the HMR require multiple pressure tests to be conducted on a single lot of DOT 2Q containers. The manufacturer is responsible for selecting the appropriate pressure test method to use on the single container selected from each lot. Therefore, if a manufacturer chooses to use a hydraulic pressure test method and the container does not burst below 270 psig, the lot of DOT 2Q containers passes the pressure test requirement. However, if a manufacturer chooses to use a heat-to-burst test method and the container bursts below 270 psig, the lot of DOT 2’Q containers fails the pressure test requirement and must be rejected. In that event, 10 additional containers may be selected at random from the same lot and subjected to the test under which the failure occurred. If any of the 10 additional containers fails the test, the lot of DOT 2Q containers must be rejected.

If you would like to propose a change, to the HMR, you may submit a petition for rulemaking following procedures outlined in § 106.95.

I hope this information is helpful. Please contact us if we can be of further assistance.



John A. Gale
Chief Standards Development
Office of Hazardous Materials Standards

173.306(a)(3)i, 178.33a-8

Regulation Sections

Section Subject
173.306 Limited quantities of compressed gases
178.33a-8 Tests