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Interpretation Response #21-0066

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Robert L. Beck

Location State: CA Country: US

View the Interpretation Document

Response text:

September 14, 2021

Mr. Robert L. Beck
10898 Osceola Mills Street
Las Vegas, NV 89141

Reference No. 21-0066

Dear Mr. Beck:

This letter is in response to your June 17, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to test system component calibration requirements in Compressed Gas Association (CGA) Pamphlet C-1, "Methods for Pressure Testing Compressed Gas Cylinders."

We have paraphrased and answered your questions as follows:

Q1. You ask whether the master gauge in the computer system must be of the same or greater accuracy as the pressure indicating device (PID).

A1. The answer is yes. CGA C-1 states that a master gauge is a PID that is used as a calibration standard and has an accuracy grade equal to or better than the requirement for the PID to be checked.

Q2. You ask whether the scale used as an expansion indicating device (EID) requires daily verification.

A2. The answer is yes. CGA C-1 states that the verification of the accuracy of these devices shall be accomplished daily in conjunction with the total test system verification.

Q3. You ask whether the weights for the EID require annual recalibration.

A3. The answer is no. CGA C-1 does not specify whether the weights for the EID system recalibration require annual recalibration; however, it states that recertification may be performed by the cylinder manufacturer or the requalification facility following the device manufacturer’s guidelines for recalibration.

Q4. You ask whether the verification of the EID must be documented.

A4. CGA-1 does not contain specific recordkeeping requirements for EID recalibration. However, please note that the daily accuracy verification of the requalification system must be documented each day requalifications are performed in accordance with § 180.215(b)(1). Separately, each requalifier must retain the most recent certificate of calibration for the EID, in accordance with § 180.215(b)(4).

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

180.215(b)(1), 180.215(b)(4)

Regulation Sections