This standard specifies detailed instrumental methods for the determination of carbon, hydrogen, and nitrogen content in lignite, bituminous coal, and anthracite. The core approach involves rapid measurement using modern instrumental techniques, with carbon and hydrogen detected via infrared spectroscopy and nitrogen content measured by thermal conductivity. Compared to traditional methods, this approach offers a high degree of automation, enabling batch processing of multiple samples and significantly improving testing efficiency. The relevant testing instruments primarily refer to carbon-hydrogen-nitrogen analyzers, such as the SDCHN series and other models compliant with this standard. These instruments implement the aforementioned methods through automated sampling, integrated gas circuits, and precision sensors, with each test requiring only a few minutes. The standard covers method principles, reagents and materials, instrument operation, calibration procedures, result calculation, and precision requirements.