本文件针对单相气体测量提供了以下方面的指导，以允许用户实现目标测量不确定度:-流量计类型的选择:差压、位移、超声波、科里奥利、涡流、涡轮、热力等；-测量流体财产和流动条件的相关仪器，如压力和温度变送器、密度计、气相色谱仪获得和使用气体成分或其他分析数据-测量系统的设计和安装要求；-流量计及其相关附件仪表的检查、验证和校准规程； -用实例说明方法的简化不确定度计算。

This document, for single-phase gas measurement, provides guidance in the following areas to allow the user to achieve a targeted uncertainty of measurement:- selection of flow meter type: differential pressure, displacement, ultrasonic, Coriolis, vortex, turbine, thermal, and others;- associated instrumentation for measuring fluid properties and flowing conditions, such as pressure and temperature transmitters, densitometers, gas chromatographs;- obtaining and use of gas composition or other analytical data;-design and installation requirements of the measurement system;- inspection, verification, and calibration practices of flow meters and their associated accessory instrumentation;- simplified uncertainty calculations with examples to illustrate the methodology.