瓦斯含量是煤与瓦斯突出危险预测、煤层瓦斯资源量估算、矿井瓦斯治理工程设计的重要参数。围绕如何在大区域准确快速测定煤层瓦斯含量，依托国家科技重大专项、国家自然科学基金和煤炭企业联合基金等项目科技攻关，在取样、测试方面取得了一定进展。主要表现在如下4个方面：①煤层瓦斯含量测定取样经历了孔口接样、岩心管定点取样、压力引射定点取样和密闭取样4个阶段，密闭取样装备保压能力达到11.5 MPa，煤心直径达到38 mm；②针对不同煤层地质条件，发展形成了顺煤层定向长钻孔密闭取样、底板穿层钻孔密闭取样和顶（底）板梳状定向长钻孔密闭取样3种取样技术；③在河南焦作和山西晋城矿区硬煤层中，顺层定向长钻孔取样深度达到516 m，密闭取样法测得煤层瓦斯含量较常规取样法分别平均提高了0.44倍和1.04倍。在安徽淮南矿区碎软煤层中，穿层钻孔密闭取样深度达到209 m，测得煤层瓦斯含量较常规取样法平均提高了0.26倍；在安徽淮北矿区碎软煤层中，顶（底）板梳状钻孔密闭取样深度达到484 m，测得煤层瓦斯含量较常规取样法平均提高了0.19倍，密闭取样法在煤层瓦斯含量测定精度、探测范围上优于常规取样法；④在瓦斯含量测试方面，除了传统解吸法测试，发展了系列煤矿井下瓦斯含量快速测试装备，可实现最快30 min内测得煤层瓦斯含量，一般用于百米孔内的瓦斯含量测试。提出了煤层瓦斯含量测定密闭取样装备需向小型化、轻量化的方向发展，并能实现随钻密闭取样。在测试上，应根据实际情况确定合理的解吸终止限，并将测试装备和密闭取样装备进一步结合，以实现深孔瓦斯含量快速准确测定。密闭取样技术已成为煤层瓦斯含量大区域精准勘查、预测的主要手段，是煤炭安全高效开采的重要技术保障。

Gas content is an important parameter for the prediction of coal and gas outburst risk, the estimation of coal seam gas resource, and the design of mine gas control engineering. Focusing on how to accurately and quickly determine the gas content of coal seams in large area, and relying on the National Science and Technology Major Project, the National Natural Science Foundation of China, the Joint Fund of Coal Enterprises and other projects to develop scientific and technological research, some progress had been made in sampling and testing, and the main manifestations were as follows. ① The development of sampling for gas content determination in coal seam has gone through four stages, namely, orifice sampling, core tube spot sampling, pressure injection spot sampling, and sealed sampling. The pressure holding capacity of the sealed sampling equipment reached 11.5 MPa, and the diameter of coal core reached 38 mm. ② According to different geological conditions of coal seams, three types of sampling techniques had been developed, including directional long borehole sealed sampling along coal seam, floor cross-layer borehole sealed sampling, and comb-shaped directional long borehole sealed sampling in roof or floor. ③ In the hard coal seams of Jiaozuo mining area in Henan Province and Jincheng mining area in Shanxi Province, the sampling depth of the directional long borehole along the seam reached 516 m, and the gas content of the coal seam measured by the sealed sampling method was increased by an average of 0.44 and 1.04 times compared with the conventional sampling method, respectively. In the broken soft coal seam of the Huainan mining area in Anhui Province, the sealed sampling depth of the cross-layer borehole reached 209 m, and the measured gas content of the coal seam was increased by 0.26 times on average compared with the conventional sampling method. In the broken soft coal seam of the Huaibei mining area in Anhui Province, the comb drilling sealed sampling depth reached 484 m in roof or floor, and the measured coal seam gas content was 0.19 times higher than that of the conventional sampling method. The sealed sampling method was superior than the conventional sampling method in terms of determination accuracy and detection range of coal seam gas content. ④ In terms of gas content testing, in addition to the traditional natural desorption test, a series of coal mine gas content rapid test equipment had been developed, which can measure the gas content of coal seam within 30 min at the earliest, and was generally used for gas content testing in 100-meter hole. It is proposed that the sealed sampling equipment for coal seam gas content determination needs to be developed in the direction of miniaturization and lightweight, and it can realize sealed sampling with the drilling. In the test, a reasonable desorption termination limit should be determined according to the actual situation, and the testing equipment and sealed sampling equipment should be further combined to achieve the rapid and accurate determination of gas content in deep hole. Sealed sampling technology has become the main means of accurate exploration and prediction of coal seam gas content in large areas, and it is an important technical guarantee for the safe and efficient coal mining.