1.1 本试验方法包括测定表1所示成分范围内天然气和类似气体混合物的热值 表1 和 表2 这涵盖了火炬成分，但无意限制在火炬气体中测量的成分。 1.2 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.3 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法提供了一种连续测量燃气总热值的准确可靠程序，用于法规遵从性、监管转移和过程控制。 5.2 一些符合本试验方法中规定要求的仪器的响应时间约为1分钟或更少，并可用于在线测量和控制。 5.3 该方法对氧和非烷烃燃料的存在很敏感。对于未列出的成分和成分范围不在 表1 和 表2 为了获得正确的结果，可能需要对方法进行修改并更改所使用的一种或多种标定气体。

1.1 This test method covers the determination of the heating value of natural gases and similar gaseous mixtures within the range of composition shown in Table 1 , and Table 2 that covers flare components but is not intended to limit the components to be measured in flare gases. 1.2 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.3 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. ====== Significance And Use ====== 5.1 This test method provides an accurate and reliable procedure to measure the total heating value of a fuel gas, on a continuous basis, which is used for regulatory compliance, custody transfer, and process control. 5.2 Some instruments which conform to the requirements set forth in this test method can have response times on the order of 1 min or less and can be used for on-line measurement and control. 5.3 The method is sensitive to the presence of oxygen and nonparaffin fuels. For components not listed and composition ranges that fall outside those in Table 1 and Table 2 , modifications in the method and changes to the calibration gas or gasses being used may be required to obtain correct results.