Abstract: Objective To understand the performance of measuring instruments used by occupational hygiene technical service organizations engaged in hand-transmitted vibration measurement in workplaces in Guangdong Province. Methods In September 2023,a cluster sampling method was used to collect and analyze information on the latest calibration/verification certificates of 93 occupational hygiene technical service organizations engaged in hand-transmitted vibration measurement in workplaces in Guangdong Province,with one instrument each. Using SV111 portable vibration calibrator as the verification standard source,the error between the measured values and the standard values of the hand-transmitted vibration measuring instruments of each organizations was verified at three acceleration levels of 15.92 Hz,1 m/s²,79.58 Hz,10 m/s²,and 159.20 Hz,10 m/s². A score ≥11 points is considered qualified,with a maximum score of 18 points. Results The calibration or verification results of instruments from 93 institutions were all within the maximum allowable deviation range. However,out of 93 calibration or verification certificates issued by metrology institutions,85(91.4%) were based on the calibration regulations for vibration instruments,8(8.6%) were based on incorrect calibration regulations,including regulations for other instruments,non calibration regulations,expired and obsolete calibration regulations. In the instrument verification results of 93 institutions,the median(M) in the three axes(X,Y,Z) of 15.92 Hz,1 m/s² were 0.976,0.978,and 0.971 m/s²,respectively. The M values of 79.58 Hz,10 m/s² were 9.901,9.901,and 9.851 m/s²,respectively. The M values of 159.20 Hz,10 m/s² were 9.931,9.933,and 9.884 m/s²,respectively. The M score for 93 institutions was 18 points,with a total of 78 instruments(83.9%) judged as qualified and 15 instruments(16.1%) judged as unqualified. There were no statistically significant differences in the qualification rate of measuring instruments between non private organizations and private organizations,as well as between single axis measuring mode instruments and three-axis measuring mode instruments(all P>0.05). Conclusion The accuracy of hand transmitted vibration measurement results in some occupational health technical service organizations in Guangdong Province is questionable,and conducting hand transmitted vibration measurement instrument verification using a stable standard vibration source can reveal issues within the organization.

Key words: Hand transmitted vibration, Measuring instrument, Standard vibration source, Multi frequency verification, Occupational health technical service organizations