Visit：1214 Date：2022-01-05

 At present, there are three types of sphygmomanometers on the market.  
1. Traditional mercury column (mercury column) sphygmomanometer. There are desktop and vertical sphygmomanometers. The height of the vertical sphygmomanometer can be adjusted arbitrarily. The results are reliable and most commonly used, but the volume is slightly large, which is inconvenient to carry, and it is easy to cause mercury leakage during carrying, which will affect the accuracy. Therefore, before each measurement, it is necessary to check whether the mercury convex surface in the graduated tube is exactly at the zero position of the scale. After pressure measurement, tilt the sphygmomanometer 45 degrees to the right and turn off the switch to avoid mercury leakage.  
 
2. Barometer (spring) sphygmomanometer. The use of air pressure pump for pressure measurement has the advantages of small volume, convenient carrying and no mercury leakage. The sphygmomanometer is loading the sphygmomanometer, but with the increase of application times, the accuracy of the results will be affected due to the change of spring properties, so it needs to be calibrated with the standard mercury sphygmomanometer regularly.  
 
3. Electronic sphygmomanometer. Electronic sphygmomanometer uses electronic pressure and pulse sensors (instead of stethoscope) to identify pressure and pulse signals and express them in digital form. The upper part of the screen is systolic pressure, and the lower part is diastolic pressure and pulse number. The utility model has the advantages of simple operation, intuitive reading, automatic measurement by pressing the button, and is suitable for family use. However, the electronic sphygmomanometer also has the disadvantage of high error rate, which also needs to be calibrated based on the standard mercury sphygmomanometer.