Contribution
Prevalence of Airborne Ultrasound in Public Spaces
* Presenting author
Abstract:
Since its initial industrial applications in the early 20th century, airborne ultrasound has become increasingly prevalent, not only in workplaces but also in public spaces. This expansion prompted early research into the health effects of ultrasound exposure on industrial workers, leading to the establishment of interim guidelines in 1984 that set occupational and public exposure limits. Yet, over the past 40 years, ultrasound technology has evolved significantly, with applications proliferating in both industrial and public settings. Consequently, the applicability of these guidelines is under question. In response, the National Metrology Institute of Germany (PTB) was commissioned to assess airborne ultrasound exposure in public spaces. Following an extensive literature review, numerous in-situ ultrasound measurements were conducted in publicly accessible locations, including an airport, a train station, and a shopping centre.Additionally, common household devices were examined. This paper presents the first results of these in-situ measurements, revealing several new and at times unexpected sources of airborne ultrasound.