DIGITALNA ARHIVA ŠUMARSKOG LISTA
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all four distances was one hour. A total of 360 sample measurement values were obtained by taking the arithmetic mean of the values of each 10 seconds for the measurement period (Figure 4). The data of carbon monoxide from the chainsaw’s exhaust was measured while the engine was idling at each measurement. Display screen of measuring instrument were recorded using a cell phone camera (Figure 2). The recorded measurements were read from the video recording screen and were tabulated in MS Excel in the office environment. Statistical analysis – Statistička analiza The amount of CO emitted from the exhaust of the chainsaw is divided into 4 main classes according to the distance and 12 subgroups according to the exposure time (Table 4). Then, the relation between the amount of CO of the chainsaw and the distances and the exposure time was examined with a One-Way ANOVA at a significance level of 0.05. The difference between the averages was evaluated by Duncan’s multiple comparison test. To study the relationship between variables, statistical calculations were performed by using the SPSS software package using Pearson correlation test (SPSS 2012). RESULTS REZULTATI Results of variance analysis indicated to significant differences between the operator’s distance to CO gas and the amount of CO gas exposure. In addition, CO exposures showed a statistically homogeneous distribution (p<0.05). While the average CO gas exposure was the highest (1683.04 ppm) at 0 cm = 1, it gradually decreased as the distance increased (Table 5). According to Duncan’s multiple comparison test results, the operator was exposed to CO gas at the highest rate (1693.04 ppm-D) at 0 cm. As the distance increases, the average amount of CO exposed have decreased from 10 cm (343.58 ppm-C) to 20 cm (252.34 ppm-B) and 30 cm (86.49 ppm-A), respectively. The operator was exposed to CO gas at a minimum close-range distance of 30 cm. There is a significant difference between distance and CO exposure time at the 95% confidence level. According to the results of the analysis of variance, the amount of CO gas in the first 10 minutes (Group 2) was the highest when exposed to CO gas at 0 cm (Table 5). The same happens when exposed from a distance of 10 cm. In the first 5 minutes, the operator was exposed to the lowest amount of CO gas from 20 cm, but as time increases, the amount of CO gas increase. Considering the CO exposure measurements at a distance of 30 cm from the exhaust outlet, the CO emissions of the chainsaw were higher in the first 5 minutes, while the average amount of CO decreased after the first 5 minutes (Table 6). The reason why the amount of gas exposure decreases in the opposite direction as time increases is because the measurement is carried out under open weather conditions and is affected by wind speed. According to Duncan’s multiple comparison test results, the operator can be exposed to CO equally and at the highest rate (F) in groups 2 and 3, while groups 12, 11, 10, 6 and 7 were exposed to CO at the same degree and at the lowest rate (A) (Table 6). A correlation test was also conducted to determine the relationship between the distance to exhaust and the amount of CO exposed and the duration of exposure (Figure 5). According to the results, it is found that there is a very strong |