Effect of race upon noise induced hearing pattern

Hearing of 2 groups of workers were compared to study the effect of race on noise induced deafness. The first group consisted of 40 Filipino workers and the other included 40 Indian workers. Matching was done for type of noise dosimetry were done for all workers included in the study. The mean age of workers was 33.87 +/- 4.02 years, while they spent 5.67 +/- 2.24 years exposed to noise which had an average level of 92.85 +/- 6.07 dB. The results indicated that both groups had a similar audiogram pattern for both right and left ears. No significant differences were observed between the 2 groups regarding the level of hearing at the measured frequencies. Both groups showed mild functional loss of hearing with no significant differences of the mean functional hearing loss of Filipinos [4.4017 +/- 4.138%] and Indians [4.4444 +/- 3.999%]

Comparison of hearing effects of different noise patterns

In this study the effects on hearing induced by occupational exposure to continuous noise with added impulses, continuous noise and intermittent noise with varying intensity were compared. Personal noise dosimetry was used to measure the level of noise exposure and pure tone audiometry was utilized to measure hearing threshold. The results indicated that these types of noise produced similar audiographic patterns. Continuous noise with added impulses affected both high and low frequencies of hearing in contrast to the other 2 types which affected mainly the high frequencies. Effects of continuous noise with added impulses appear at a shorter duration of exposure than the other types of noise