4.1 This test method provides an accurate and reliable method to measure the total calorific value of a fuel gas, on a continuous basis, which is used for regulatory compliance, custody transfer, and process control.

1.1 This test method covers the determination with the continuous recording calorimeter (Note 1) of the total calorific (heating) value of fuel gas produced or sold in the natural gas range from 900 to 1200 Btu/standard ft³.

Note 1: An extensive investigation of the accuracy of the Cutler-Hammer recording gas calorimeter, when used with gases of high heating value, was made by the National Bureau of Standards in 1957 under a research project sponsored by the American Gas Association.

1.2 The subjects covered in this test method appear in the following sections:

Sections

Air-Gas Ratio Test

11

Apparatus

 5

Basis of Measurement

14

Cold Balance Test

10

Compensation of Complicating Factors

13

Condition of Gas Sample

 7

Definitions

 2

Installation of Apparatus

 6

Maintenance

Appendix X1

Operating Precautions

Appendix X2

Operation and Checking of Apparatus

 9

Precision

15

Scope

 1

Significance and Use

 4

Standardization of Calorimeter

12

Standardization, Preliminary, of Calorimeter by Hydrogen

 8

Summary of Test Method

 3

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.