Methodology issues of ultrasonic noise exposure assessment

Ultrasonic noise is on the list of harmful factors in the work environment in many countries. In the frequency range above 20 kHz there is a shortage of clear and complete information about the factors affecting the measurement results of sound pressure level. Until recently, the ultrasonic noise measurement methods and determining the uncertainty of measurements were combined with audible noise measurement methods (ISO 9612:1997). Currently there are no up-to-date international standards for the measurement of ultrasonic noise in the workplace. The article describes the applicability of the selected points of the ISO 9612:2009 standard in the measurement of ultrasonic noise and attention was drawn to items that are not fully examined. (C) 2012 Institute of Noise Control Engineering.