Commonly known as "Mosquito alarms" they emit high frequencies that adults have lost the ability to hear. I've never read a study that showed they cause permane

Commonly known as "Mosquito alarms" they emit high frequencies that adults have lost the ability to hear. I've never read a study that showed they cause permanent hearing loss, especially in adults, but it's unlikely someone would be exposed to them for long (vs the hypothesis here, that the diplomats were continually undergoing exposure).