Interpretation Response #17-0052

Interpretation Response Details

August 30, 2017

Mr. Ronald C. Mauney
Senior Product Design Engineer
Kidde Residential and Commercial Division
1016 Corporate Park Drive
Mebane, NC 27303

Reference No. 17-0052

Dear Mr. Mauney:

This letter is in response to your April 28, 2017, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to fire extinguishers. Specifically, you reference § 173.309(c)(4) of the HMR, which requires a fire extinguisher be tested, without evidence of failure or damage, to at least three times its charged pressure at 21 °C (70 °F) but not less than 825 kPa before initial shipment, and be marked to indicate the year of the test within 90 days of the actual date of the original test. You ask if this regulation intends for the testing stamp year to reflect the year the fire extinguisher was tested, as opposed to the year the cylinder was manufactured.

The intention of the testing requirement in § 173.309(c)(4) is to mark the cylinder with the year the fire extinguisher was tested and place the marking on the fire extinguisher within 90 days of the actual date of the original test. For example, if a cylinder was manufactured in 2015, subjected to testing in 2017, and thus put into use as a fire extinguisher; the stamp should be marked as 2017 within 90 days of such testing.

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

Sincerely,

T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

173.309(c)(4)

Regulation Sections