The vibration characteristics of hand-held riveting hammers and bucking bars used in the aircraft industry were measured and recorded for frequencies from 6 Hz to 10 MHz. Three different measuring systems had to be used. Up to about 1 kHz a displacement transducer was used, up to about 50 kHz a piezoelectric accelerometer was used, and in the megahertz region an ultrasonic probe was used. The signals were analyzed according to the guidelines of the International Organization for Standardization (ISO/DIS 5349), and also according to methods common in environmental engineering. The weighted acceleration according to ISO/DIS 5349 was between 10 and 11 m/s² for typical riveting tools. Very high acceleration values were obtained for frequencies above those specified in ISO/DIS 5349. In a group of 288 riveters, about 50% showed symptoms indicating Raynaud's phenomenon after about 10 years of work, although the daily exposure of riveting tools was about 1 min/d. The investigation showed that special precautions must be taken to measure the acceleration of percussion tools and that the risk criteria in ISO/DIS 5349 do not cover all the risks connected with percussion tools.
Keywords: acceleration, exposure, high-frequency vibration, narrow band, one-third octave band, pneumatic hammer, response analysis, risk assessment, vibration intensity, white finger