SL 410-2007 "Falling Hammer Calibration Regulations" are applicable to the first calibration, subsequent calibration and in-use calibration of falling hammers. This standard refers to "Geotextile and related products dynamic perforation test, falling hammer method" (GB/T 17630), which aims to standardize the calibration conditions, items, methods, result processing and calibration cycle of falling hammers to improve the calibration mass. Before performing the calibration, it is necessary to fully prepare and strictly implement the operating procedures to ensure the integrity and Reliability of the calibration results. In addition, the calibration work of falling hammers shall comply with the provisions of this standard, and shall also comply with the relevant national standards in force. As a special instrument, drop weight meter is used to determine the penetration aperture of geosynthetics.