Issues and recent research on VHF sound exposure with consideration for young people's hearing perception

We define VHF sound as airborne sound that may be audible to humans above 16 kHz. It has been reported in recent studies that VHF sounds can be annoying when audible. We have therefore carried out various research studies to ensure the safe use of VHF sounds. One of the aim of this study is to obtain basic data for developing guidelines for VHF sound exposure, if necessary.These include measurements of hearing thresholds in the VHF range, ABR measurements, HRTF measurements and acoustic measurements for simulation and current situation of exposure regarding the effect of hair. This paper reports on recent trends in VHF sound exposure in Japan and several studies on the perceptions of young people's hearing of VHF sounds.