Can ultrasonics cause damage to hearing? Are there any other effects on the body?
Ultrasonic cleaning equipment utilizes high energy sound waves at frequencies above those audible to humans to enhance the chemical and mechanical cleaning effects of liquids. The ultrasonic energy, although high in power, has no measurable impact on human auditory senses – in fact, there are no established time weighted average exposure limits for frequencies above 20kHz (20,000 cycles per second) . The frequencies of concern are the audible sub-harmonics of the ultrasonic primary frequency. These are produced due to sympathetic resonance of various components of the ultrasonic equipment which may include the cleaning tank, the enclosure panels, lids and other features. Pumps, blowers, and other ancillary equipment also contribute to the overall noise produced by the unit. In that regard, ultrasonic cleaning equipment is no different than a machine tool or any other piece of equipment found in the industrial environment. Ultrasound of the intensity that can be transmitted through the
