Background: Noise prevailing in the non-occupational environment, such as that experienced in disco or rock concerts may be dangerous to the condition of the human hearing organ. The existing methods for assessing the risk of hearing loss (e.g., specified in ISO 1999:1990) fails to consider the contribution of non-occupational noise to the overall noise exposure. The fact that there is no generally accepted method for assessing the contribution of individual exposures to non-occupational noise to be used in epidemiological studies is one of the reasons that the effect of the quoted ISO procedure is limited. The aim of this study was to develop a method enabling quantitative assessment of the individual level of non-occupational noise exposure and estimation of the exposure uncertainty in large groups of people.
Material and methods: Based on the available literature data and our own results, we established a database on noise levels associated with typical circumstances prevailing in the general environment. A questionnaire was developed to enable collection of data essential for defining individual exposures to non-occupational noise. Using the questionnaire data, a procedure for assessing the level of non-occupational noise exposure was developed and its reliability was determined by assessing the repeatability of the results of two determinations performed every three weeks and comparing the calculated levels of the noise exposures with the true levels.
Results: The values of individual non-occupational noise exposure, referred to 8h (LEX, 8h) in the study group of people, using the proposed methods ranged between 69 dB and 80 dB. This method allows to assess individual non-occupational exposures to noise at 1-2 dB error relative to the measured levels. The uncertainty of the method is within 4 dB.
Conclusions: The proposed method enables a reliable assessment of non-occupational exposure to non-occupational noise and may be successfully applied in epidemiological studies.