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Interpretation Response #09-0198 ([UPS Aircraft Maintenance Hangar] [Mr. Robert A. Stewart])

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

Interpretation Response Details

Response Publish Date:

Company Name: UPS Aircraft Maintenance Hangar

Individual Name: Mr. Robert A. Stewart

Location State: KY Country: US

View the Interpretation Document

Response text:

December 14, 2009




Mr. Robert A. Stewart

UPS Component Shop Supervisor

UPS Hydrostatic Shop

UPS Aircraft Maintenance Hangar

750 Grade Lane

Louisville, KY 40213

Ref. No.: 09-0198

Dear Mr. Stewart:

This is in reference to your August 13, 2009 letter in which you again ask about possible tolerance requirements for the permanent expansion reading for the calibrated cylinder.

As stated in my previous responses, the cylinder requalifier must use a calibrated cylinder or other approved method to verify the accuracy of the test equipment system. When the calibrated cylinder is pressurized, the test equipment must be verified as accurate within ± 1.0% of the calibrated cylinder's pressure and the corresponding expansion value shown on the cylinder calibration certificate. When the pressure is released, this calibration process requires that the calibrated cylinder exhibit no permanent expansion as specifically stated in

§ 180.205(g)(4).

With regard to your reference to the Compressed Gas Association (CGA) C-1, currently the HMR do not incorporate the publication by reference. We may consider incorporating by reference this publication or certain provisions of the CGA C-1 publication in a future rulemaking.

I hope this information is helpful. Please contact us if you have additional questions.

Sincerely yours,

Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
180.205 General requirements for requalification of specification cylinders