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Interpretation Response #07-0059 ([UPS Hydrostatic Shop] [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 Hydrostatic Shop

Individual Name: Mr. Robert A. Stewart 

Location State: KY Country: US

View the Interpretation Document

Response text:

Mar 30, 2007


Mr. Robert A. Stewart                Reference No. 07-0059
UPS Component Shop Supervisor       
UPS Hydrostatic Shop
UPS Aircraft Maintenance Hangar
750 Grade Lane
Louisville, KY 40213

Dear Mr. Stewart:

This is in reference to your March 9, 2007 letter in which you again ask about possible tolerance requirements for the permanent expansion reading for the calibrated cylinder.

As stated in my February 15, 2007 letter (ref. No.: 07-0002), 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, 1.his calibration process requires that the calibrated cylinder exhibit no permanent expansion as specifically stated in § 180.205(g)(4).

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

180.205 (g)(4)

Regulation Sections

Section Subject
180.205 General requirements for requalification of specification cylinders