本方法包括选择合适的天然气和天然气液体（NGL）参考标准、制备使用标准、验证制造商报告的成分准确性的推荐程序，以及这些标准的适当护理和储存，以确保其在使用期间的完整性和寿命。

This method covers the recommended procedures for selecting the proper Natural Gas and Natural Gas Liquids (NGL) Reference Standards, preparing the standards for use, verifying the accuracy of composition as reported by the manufacturer, and the proper care and storage of those standards to insure their integrity and longevity as long as they are in use.