[Assessment of low frequency noise annoyance in steering premises according to subjective annoyance rating by workers. A pilot study]. / Ocena uciazliwosci halasu niskoczestotliwosciowego w pomieszczeniach sterowniczych wg subiektywnej oceny pracowników--wyniki badan pilotazowych.

ABSTRACT

The study covered 192 workers aged 26-62 years (mean 41 +/- 6), employed at workposts in the control rooms. A questionnaire was applied as a main tool of the study. The aim of the study was subjective annoyance rating of low frequency noise at workplaces on a 100-degree rating scale. Using the same scale, the study subjects rated annoyance of reference wide-band noise (60 +/- 2, 70 +/- 2, 75 +/- 2 and 80 +/- 2 dB(A)) and reference low frequency noise (65 +/- 2, 70 +/- 2, 75 +/- 2 and 80 +/- 2 dB(A)) reproduced by phones. Questionnaire inquires were preceded by the measurements of A-, C- and G-weighted equivalent continuous sound pressure levels (LA eq.T, LC eq,T i LG eq,T). Noise with prominent low frequency components (10-250 Hz) at A-weighted sound pressure level of 47.7-65.2 dB was assessed as more than somewhat annoying (more than 25 degrees on the 100-degree annoyance rating scale) by 70% of workers examined. No correlation between subjective annoyance rating of the noise at the workplaces and LA eq,T or LG eq,T was noted. Statistically significant correlation (r = 0.23) between subjective annoyance rating and LC eq,T was observed. The subjective rating of annoyance of the reproduced low frequency noise and wide-band noise differed significantly. Low frequency noise was rated as more annoying than wide-band noise at the same A-weighted sound pressure levels.