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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #02-0130 ([Argus Fire Control] [Bruce J. Euler])

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

Interpretation Response Details

Response Publish Date:

Company Name: Argus Fire Control

Individual Name: Bruce J. Euler

Location State: NC Country: US

View the Interpretation Document

Response text:

JUL 15, 2003

Mr. Bruce J. Euler                                         Ref. No. 02-0130
Director of Engineering
Argus Fire Control
2301 Distribution Street
Charlotte, NC 28203

Dear Mr. Euler:

This is in response to your letter requesting clarification on whether a DOT specification 39 cylinder may be used as a fire extinguisher under the Hazardous Materials Regulations (HMR;49 CFR Parts 171-180). I apologize for the delay in responding and hope it has not caused any inconvenience.

In your letter you describe a fire extinguishing system consisting of a DOT specification 39 cylinder with a volumetric capacity of 1720 ml (104 cu in), an operating pressure of 150 psi, and a minimum burst pressure of 1440 psi. This system is intended to be sold to end-users as a complete self-contained pressurized system capable of being refilled and recharged by distributors. You further state that, after the extinguishing system is discharged or emptied, it is returned to the distributor, refilled and pressurized, transported back to the end-user, and reinstalled into the system.

Your specific questions are parapharsed and answered below:

Q1. You asked if a DOT 39 cylinder may be used as a fire extinguisher under the HMR. You also
asked whether the cylinder once installed into the fire extinguishing system would be considered a nonspecification cylinder.

A1. The answer is no. Hazardous materials transported under the proper shipping name "Fire
extinguisher" must be packaged in accordance with §173.309. Section 173.309(a) allows the use of non-specification cylinders as fire extinguishers, if all criteria listed therein are met. If the requirements of § 173.309(a) cannot be met, a DOT specification 3A, 3AA, 3E, 3AL, 4B,
4BA, 4B240ET, or 4BW (§§ 178.36, 178.37, 178.42, 178.46, 178.50, 178.51, 178.55, and 178.61) cylinder must be used in accordance with § 173.309(b). In addition, although a specification cylinder is installed into an extinguishing system, the cylinder is marked to indicate conformance with the specific requirements applicable to the packaging, and thus remains a specification packaging.

Q2: You ask ifthere are special requirements applicable to cylinders used as fire extinguishers?

A2: Materials transported under the proper shipping name "Fire extinguisher" must be packaged in
accordance with §173.309.

Q3. After initial shipment and installation can this cylinder be transported for refilling or recharging if

A3. The answer is no. A DOT 39 specification cylinder charged with a hazardous material,
transported, and emptied, may not be refilled with a hazardous material and transported a second time (see § 178.65).

Q4. Does this system require requalification testing and inspection?

A4. Under the HMR, each specification cylinder used as a fire extinguisher and meeting Special
Provision 18 in § 172.102(c)(1) must be requailified. (see § 180.2090)). Additionally, each nonspecification cylinder used as a fire extinguisher must be in compliance with the retest requirements of the Occupational Safety and Health Administration Regulations of the Department of Labor, 29 CFR 1910.157(e) (see § 173.309(3)(iv)).

I trust this satifies your request. If you need additional assistance, do not hesitate to contact this office.


Susan Gorsky
Senior Transportation Regulations Specialist
Office of Hazardous Materials Standards

Regulation Sections

Section Subject
178.65 Specification 39 non-reusable (non-refillable) cylinders