This standard provides a unified test method for determining the surface tension of glass melts using the sessile drop method. It specifies a comprehensive procedure, including measurement principles, sample preparation, specific test steps, result calculation, and reporting, applicable to relevant scientific research and production quality control. The core of the sessile drop method involves calculating the surface tension by analyzing the contour of a glass melt droplet stably placed on a substrate under high temperature and a controlled atmosphere. Therefore, the key detection instruments relied upon by this method are typically comprehensive high-temperature sessile drop instruments or contact angle measuring instruments, equipped with a high-temperature furnace, a precise optical imaging system (for capturing droplet contours), and professional image analysis software.