Medical Device Reprocessing Association of Ontario (MDRAO) Practice Exam

What does cavitation refer to in the context of ultrasonic cleaning?

1. The creation of large bubbles through boiling

2. A reaction between cleaning agents and water

3. Electrical energy converted to sound waves that create small bubbles

4. The heating of water to enhance cleaning effectiveness

The correct answer is: Electrical energy converted to sound waves that create small bubbles

Cavitation in the context of ultrasonic cleaning refers to the phenomenon where sound waves create pressure changes in a liquid, leading to the formation of small bubbles. These bubbles form in areas of low pressure during the sound wave's expansion phase and subsequently collapse violently during the compression phase. This collapse generates high temperatures and immense pressure at a very localized level, which contributes to the scrubbing action that removes contaminants from surfaces. Understanding this process is crucial for grasping the effectiveness of ultrasonic cleaning technology, which relies on these small yet powerful bubbles to reach intricate geometries and crevices that traditional cleaning methods might miss. The other options do not accurately represent the mechanism of cavitation; for instance, boiling does not involve sound waves but rather the temperature increase of a liquid, while chemical reactions and heating are not specific to the cavitation process in ultrasonic cleaning.