Public Exposure to Very High Frequency Sound and Ultrasound: Do We Know the Risks?

Literature has linked very high and ultrasonic frequency sound in air to tinnitus and other “subjective” effects, including headache and nausea, for over 40 years. Very little attention has been paid to the subject in the last 30 years, however the use of these frequencies is rapidly becoming more common, and increasing numbers of adults and children are exposed to these frequencies daily, often without their knowledge. Scientific study is emerging in the health effects of prolonged exposure to these frequencies, and the safety legislation that should surround them. National and international research currently being carried out to investigate the hearing abilities of different groups, and the potential impact of exposure, is described. Safety guidelines, especially for those with more sensitive hearing such babies, children and those with hyperacusis, and also some people prone to migraine, are of particular importance.