Systematic monitoring of noise levels was carried out inside the cabin of all the Heavy Earth Moving Machineries deployed in a chromite mining complex during summer 2008 and winter 2009. The present study aimed to estimate the significance and the degree of association of the noise levels with respect to all the HEMMs. The analysis (t-test) shows that the equivalent noise (Leq) levels inside the cabin differ significantly with the test value of 85 dBA for all the HEMMs. Analysis of Variance reveals that the values of Leq are not identical with respect to the time of monitoring and also inside the cabins of different HEMMs (p<0.01). The Leq is the most significant during third part of time monitoring inside the cabin of the dozer (p<0.01). The Chi-square test reveals that 0.752 is the highest degree of association between the dozer, p=0.000(p<0.01) and Leq levels and exists a high degree of association.