Research of noise levels emitted by two-spindle moulders

The protection of work environment from emitted noise, vibrations, gases and dust is nowdays the production process designers' main concern. This problem is gradually winning adequate attention in Croatia, too. Work environment protection problems are particularly emphasized in woodworking industry. At the Faculty of Forestry in Zagreb protection from noise and vibration has been systematically studied for more than 20 years now. The paper presents the results of routine measurements regularly carried out at wood-working plants by researchers of the Department for Mechanical Engineering of the Faculty of Forestry, University ofZagreb. Presented are the measured noise levels emitted by two-spindle moulders. Because of the high level of the emitted noise, the moulders were placed in a separate room. But, the small room volume and the proximity of reflecting surfaces resulted in a noise level significantly above the noise level limits. The measurements covered all operator positions. According to the results of the measurements the operators, depending on the position, should not be exposed for more than 1/4 to 1 hour without adequate personal protection. In order to optimize personal protection the octave band analysis was carried out.