Assessment of annoyance from low frequency and broadband noises.

OBJECTIVES

It has been shown that low frequency noise (LFN), defined as broadband noise with dominant content of low frequencies (10-250 Hz), may be annoying to exposed subjects. The aim of the study was to compare the degree of annoyance caused by LFN with that caused by broadband noise (BBN) without dominant low frequency components at similar A-weighted sound pressure levels.

MATERIALS AND METHODS

Subjects included in the study were 145 male employees of the control rooms. They were exposed to noise through headphones at gradually increasing dB A-weighted sound pressure levels within the range of 62-84 dB. Annoyance rating was based on a 100-score graphical scale.

RESULTS

LFN was rated as significantly more annoying than BBN at the comparable A-weighted sound pressure levels. The annoyance assessment of either noise did not depend on age, length of employment or the level of exposure to noise at a current workplace.

CONCLUSIONS

LFN represents a higher risk of influencing human well-being than regular BBN and should be considered in the occupational exposure assessment.