During airborne ultrasound surveys, high frequency acoustic wave energy is collected from its source and analyzed. Source initiated energy testing is ideal for monitoring air and gas leak detection, non-driven rotating mechanical systems, and many electrical systems.

One benefit ultrasound emission testing offers over many other PdM technologies is that direct contact is not always required and skilled testing professionals can scan large areas quickly from safe locations. In some cases, engineers can even perform detailed ultrasound waveform analysis remotely. For electrical systems, ultrasonic testing is often an ideal technology when used in conjunction with IR thermography due to the fact that together, the spectrum of potential failure modes is expanded exponentially.