A study on noise levels of machinery used in lumber industry enterprises

The aim of this study is to help to create a healthier environment by measuring the noise levels in the furniture and lumber sectors of forest products industry. In this study, noise measurement for approximately 3 min has been conducted in 4 measurement spots in the side of the machinery, in the factory entrance and in full and empty state for each machinery; from 3 different chosen spots in enterprises producing lumber. Measurements have been recorded as 720, from each machine as 36 measurements, with the condition to be recorded every 5 sec for 3 min. For this purpose, noise measurements have been carried out in 17 workplaces producing lumber and results have been compared statistically. As a result of the obtained findings, it is understood that the noise levels of thickness machinery don’t exceed the value for the upper limit stated in the regulations. However, vertical wood band sawmill and band saw machines have been observed to go over this limit. Besides, some factors of planning and multi slitting machine don’t exceed this limit, some of them exceed. As a result, it has been conducted that when noise levels of machinery used in the lumber industry enterprises exceed the upper limit stated in the regulations, they can pose a serious threat to human health.

Study on concentrations of acids and alcohols emitted by pinus radiata during high-temperature drying

The purpose of this paper is to investigate the influence of kiln temperature, relative humidity and wood moisture content on the content of acid and alcohol released in the drying process of high temperature kiln by studying the radiated pine sawn timber of 40mm thickness. The drying temperature was between 101°C and 115°C, the relative humidity in the drying kiln was reduced from 86.1% to 39.6%, the moisture content of the lumber was reduced from 106.16% to 11.98%, and gas extraction was executed nine times with an extraction speed of 1.0 L•min-1 and a sampling time of 30 min. The concentrations of acids and alcohols were analyzed by HPLC. The results showed that the concentrations of formic acid, acetic acid, and methanol emitted in the kiln during drying were 215.6-748.2, 4148.8-16803.2, and 6381.9-15648.9 mg•m-3, respectively, and these concentrations were significantly higher than the relevant standards. The concentrations of the emitted formic acid and acetic acid were proportional to the drying temperature, the concentrations of the emitted formic acid and acetic acid were inversely proportional to the relative humidity in the kiln and the moisture content of the lumber. The concentration of the emitted methanol was independent of the drying temperature, relative humidity in the kiln, and moisture content of the lumber. It is therefore suggested that formic acid, acetic acid, and methanol be separately recovered during the high-temperature drying of Pinus radiata lumber.