OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
Figure: 1(c) Effect of Workplace Temperature on raw data and S/N ratio
Figure 1(a, b, c) depicts the change in Heart Rate by the worker during MMH task with respect to the Worker
Age, work time duration and workplace temperature. From figure 1(a) it was concluded that as the age of worker
increases; the Heart Rate of the worker also increases during MMH task. The slope of curve for the age range of
20 to 30 was more than between 30 to 40 years range, which means that the HR increases continuously with age
but with a large extent up to age of 30 and after that somewhat less extent as compare to previous one. Wright
(1999) also concluded that younger workers can carry more load than that of older workers. It can be observed
from Figure 1(b) that with the increase in the work Time Duration the HR of the worker also increases. The slope
of curve between Work Time Duration range of 9 to 13 minutes was more than the slope between 13 to 17
minutes work time duration range. Marras (2005) also concluded that the increase in time duration will affects
the human comfort. From figure 1(c) it can be seen that as the temperature of the work place increases the HR
also increases. For the Temperature range between 20°C to 27°C the change in slope of HR was less as compare
to range between 27°C to 34°C, which implies that the high temperature will have a high effect on the human
working capability and HR of worker. For the temperature range between 20°C to 27°C the HR increases with
less extent as compare to range of 27°C to 34°C. It was observed that the low temperature zone (20°C to 27°C)
was comfortable zone for MMH than the high temperature zone (27°C to 34°C). Snook (2010) also concluded
that increase in temperature will effect on increase in HR of Worker during MMH.
Table 5: ANOVA S/N (HR)
Source SS DOF V F-Ratio SS' P (%)
Worker Age 9.96 2 4.98
*
59.75 9.79 74.12
Work Time Duration 0.61 2 0.3 3.64 0.44 --
Work Place Temperature 2.48 2 1.24 14.87 -- --
Error 0.17 2 0.08 -- 3.42 25.88
Total 13.21 8 -- -- 13.2 100
*Significant at 95% confidence level, P (%): Percentage of contribution; F Table value: 19,
SS: Sum of squares; DOF: Degree of Freedom; V: Variance; SS’: Pure Sum of Squares
Table 6: ANOVA RAW (HR)
Source SS DOF V F-Ratio SS' P (%)
Worker Age 4797.28 2 2398.64
*
204.18 4773.79 73.51
Work Time Duration 239.13 2 119.56
*
10.18 215.63 3.32
Work Place Temperature 1222.42 2 611.21
*
52.03 1198.92 18.46
Error 234.96 20 11.75 -- 30.544 4.71
Total 6493.79 26 -- -- 6493.78 100
*Significant at 95% confidence level, P (%): Percentage of contribution; F Table value: 3.49,
SS: Sum of squares; DOF: Degree of Freedom; V: Variance; SS’: Pure Sum of Squares
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