LABORATORY AND FIELD MEASUREMENTS OF NAIL GUNS’ NOISE EMISSION

Résumé

Nail guns are heavily used in the construction industry by carpenters and roofers. These hand-held power tools expose their users to impulse noise and hand-arm vibration that are difficult to mitigate due to the user’s proximity to the tool. Thus, the choice of low noise and low vibration power tools seems to be a good strategy in order to reduce workers’ exposure to such noise and vibration. In this study, 10 nail guns were tested (8 framing and 2 roofing nailers). Both noise and vibration were studied, but only the noise aspect will be discussed in this paper. The goal of this paper is to present laboratory measurements and field measurements.

Laboratory measurements on the nail guns were performed using EN 12549. The workpiece (sawn pine wood)  was buried in a sandbox placed in a semi anechoic room where both the sound power (using 9 microphones located on a cubic measurement surface) and the sound pressure level at the worker’s ear were measured. For the field measurements, a wireless rig was developed to give freedom of movement to the workers. The workers were sampled in real work situations. Microphones on the outside of the worker’s earmuffs were used to measure the sound pressure level at the worker’s ear.

The results of both the laboratory and the field measurements are presented. The sound power levels (LwA,1s) range between 95 and 107dB(A) and the sound pressure at the worker’s ear (LpA,1s) range between 91 and 100 dB(A) for field measurements and between 85 and 98 dB(A) for the lab measurements. The complete study includes also a quantification of the different sound source using acoustic antennas and a high speed camera.