Alarm detection in noise work environments: The influence of hearing protection devices

Abstract

Industrial machines are typical noisy sources causing discomfort and risk to the workers' health. Studying in what extent individual hearing protection devices influences, or not, the perception of alarms in industrial environments and in the presence of background noise was the main aim of this work. The warning signal used was a warning signal from a textile finishing machine and the background noise was produced by a white noise generator. The tests were performed with the subjects in an audiometric booth using different hearing protection devices. The obtained results shown evidence that, under the used test conditions, earplugs and passive earmuffs were the devices showing less interference with the perception of warning signals in the presence of background noise. At the same time it was found that the active (level dependent) earmuffs interfere with the perception of the warning signal in the same conditions.