Scope of application: buffer selection should be correct, energy storage buffer (such as polyurethane, spring-type, etc.) can only be used for rated speed is not greater than 1m / s elevator, energy-consuming buffer (such as hydraulic) can be used for any rated speed of the elevator. 2, production qualifications and identification: buffer should be equipped with a nameplate or labeling, indicating the name of the manufacturing unit, model, specifications and parameters and type test agency identification, nameplate or labeling and type test certificate should be consistent with the content. 3, fixed: buffer should be fixed and reliable, car, counterweight device of the center of the crash plate and buffer center deviation is not greater than 20 mm, the same basis on the top of the buffer and the car corresponding to the distance difference is not greater than 2 mm. 4, electrical switch: energy-consuming buffer level should be correct, there is a verification plunger reset electrical safety devices. After the buffer action, return to its normal elongation position for the elevator to operate normally; the maximum time limit for the buffer to be completely reset is 120 seconds. 5、Buffer distance requirement: permanent and obvious marking should be set near the counterweight buffer, indicating that when the car is located at the top end station level position, the maximum permissible vertical distance between the counterweight device impact plate and the top surface of its buffer; and the vertical distance does not exceed the maximum permissible value.