Efeito das classes de densidades da madeira e das condições dos gumes de corte no nível de pressão sonora gerado

Abstract

Safety and comfort are paramount in work environments because they are related to worker well-being and company quality and performance. No mechanical processing of the wood is observed the presence of noises that are normally harmful to workers when they exceed the intensity and the allowed exposure time. These noises after being generated can be enhanced by the characteristics of the attacking gases like wood. The objective of this work was to i) evaluate the sound pressure level in the mechanical processing of woods of different density classes and with variation in the cutting tool wear and ii) to evaluate the risk of hearing loss of workers exposed to the sound pressure levels emitted. Continuous and / or intermittent noise data were collected through the sound pressure level meter at the Woodworking Laboratory (DCF / UFLA). Cuttings were made in the circular saw in woods of three density classes with edged and non-worn conditions. To verify the normality of the sound pressure level data, the Shapiro-Wilk test was performed at 1% of significance. The Wilcoxon test paired at 1% significance showed a significant difference in the sound pressure level when related to the three classes of wood density and cutting edge wear. The average level and noise dose values were directly proportional to the wood density and the tool edge wear. The highest sound pressure level was 117 dB (A), found for the high density class processed with the circular saw with worn edges. In general, circular saw cutting presented sound pressure levels above the allowable for all wood density classes