. . 2556 16-18 2556

The Effect of Age and Helmet on Hearing Ability of Motorcyclist

1* 2 3 1,2

10800

3 10520

E-mail: krr619@hotmail.com*

Puttapong Charoynuch1*Nantakrit Yodpijit2 and Sampasit Limnorarat3 1,2 Center for Innovation in Human Factors Engineering and Ergonomics

Department of Industrial Engineering, Faculty of Engineering,

King Mongkut's University of Technology North Bangkok10800, Thailand 3 Department of Industrial Engineering, Faculty of Engineering,

King Mongkut�sInstitude of Technology Ladkrabang E-mail: krr619@hotmail.com*

125, 250, 500, 1,000, 2,000, 4,000, 6,000 8,000 10 3 20-45 ,

46-60 60 4 , ,

. . 2556 16-18 2556

Abstract

Recent statistics on road traffic accidents indicated that motorcycle has a higher fatality and injury

rate as compared with other vehicles. Prior research suggested that motorcyclist safety could be

potentially improved by acoustic awareness research to finda better response to the environmental traffic noise. As such, a better understanding of hearing ability of motorcyclists could possibly lead to traffic

accident reduction. This study was conducted in a laboratory setting. The purpose of the study was to investigate the effect of age and motorcycle safety helmet on hearing thresholds in different frequency

ranges (125, 250, 500, 1,000, 2,000, 4,000, 6,000, and 8,000 Hz). Tenmales were recruited from three different age groups: younger (20-45 years), middle-aged (46-60 years), and older (over 60 years). Four

helmet conditions: none, half face, three-quarter, and full coverage were tested. Results indicated noise attenuation by different age groups and different helmet conditions. Hearing thresholds measured in

mean decibel levels varied across combinations of age groups and helmet conditions. A decline in

hearing ability was observed when wearing a full coverage helmet as hearing was with higher threshold. Limitations and implications of these results were discussed with respect to future study in road traffic

safety improvement.

Keywords: noise attenuation, helmet, hearing threshold

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of the HCP. The Noise Manual. 5thed. American Industrial Hygiene Association. Virginia. 2003.

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�The Measurement of Age, Age Structuring, and The LifeCourse�. Annual Review of Sociology.

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