Teachers' and Children's Experiences after an Acoustic Intervention and a Noise-Controlling Workshop in Two Elementary Classrooms.

INTRODUCTION: Treating sources of noise is a novel aspect of voice ergonomics intended to enhance the preconditions for good voice production and easy listening. OBJECTIVE: To improve experiences of listening and voice ergonomics in classrooms. METHODS: Participants were two female elementary school teachers with voice symptoms and their pupils (n = 50). Two interventions were performed: the acoustic intervention and then the workshop intervention where the teachers and pupils were active. Teachers' voice symptoms and pupils' and teachers' experiences of the interventions were elicited by questionnaire. RESULTS: The teacher with many voice symptoms experienced more annoyance from sounds and benefitted more from the interventions. After the interventions both teachers suffered fewer voice breaks and voice symptoms such as lump and mucus in the throat. The pupils reported improvement in the teachers' voice clarity and audibility (p = 0.001). Pupils aged 12-13 years were more annoyed by sounds than those aged 8-9 years (p = 0.003). The older pupils experienced less sound annoyance after both interventions and the younger ones after the workshop intervention. CONCLUSIONS: The importance of good acoustics and individuals' ability to improve voice ergonomics and listening conditions was demonstrated.

Military and leisure-time noise exposure and hearing thresholds of Finnish conscripts.

This study presents an evaluation of the total cumulative noise exposure of Finnish conscripts (N = 416) during military service. All of the conscripts underwent a hearing screening and filled out a noise exposure questionnaire at the beginning and end of their military service. Eighty-nine percent of the conscripts were exposed weekly to military noise of over 85 dBA during the service. Eighteen percent of the conscripts had already reached at the end of their military service a cumulative noise dose corresponding to noise exposure of 85 dB for 40 years. During military service, permanent hearing loss of > 20 dB in the frequency range of 0.5 to 8 kHz increased from 19 to 27% among the conscripts.

Estimated leisure-time noise exposure, hearing thresholds, and hearing symptoms of Finnish conscripts.

The aim of this study was to set up a statistical measure for determine the total cumulative noise exposure of Finnish conscripts (n = 1,054) as a result of leisure-time noise activities. All of the conscripts underwent hearing screening. The conscripts' time in noisy activities and their rating of the loudness and estimated noise levels of the activities were used as the predictors in the risk analysis. Self-reported hearing symptoms (i.e., tinnitus, pain in the ear) and hearing loss due to noise exposure were also inquired about. Twenty-seven percent of the conscripts had weekly noise exposure to > 85 dBA. Approximately 20% of the conscripts had >20 dB hearing loss in either ear in the frequency range of 0.5 to 8 kHz. The incidence of hearing symptoms seemed to correlate with an increased noise dose.