1. When conducting the test, it should be noted that the metal magnetism and surface roughness of the standard piece should be similar to the test piece. ​

2. When measuring, pay attention to keeping the side head perpendicular to the surface of the sample. ​

3. When conducting tests, pay attention to the critical thickness of the base metal. If it is greater than this thickness, the measurement will not be affected by the thickness of the base metal. ​

4. When measuring, pay attention to the influence of the curvature of the specimen on the measurement. Measurements on curved specimen surfaces are therefore unreliable. ​

5. Before measuring, pay attention to whether other electrical equipment around you will generate a magnetic field. If it does, it will interfere with the magnetic thickness measurement method. ​

6. When measuring, be careful not to measure at inner corners or near the edge of the specimen, because general thickness gauges are very sensitive to sudden changes in the surface shape of the specimen.

7. Keep the pressure constant during measurement, otherwise it will affect the measurement reading. ​

8. When conducting testing, it should be noted that the instrument probe and the test piece must be in direct contact, so the sonic thickness gauge is cleaning the attached material on the opposite side.