spatial average intensity
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Related to spatial average intensity: temporal average intensity
spatial average intensityAbbreviation: SAI
The measure of power per unit area of ultrasound application, expressed in watts per square centimeter (w/cm2). The spatial average intensity is calculated by dividing the ultrasonic output, expressed in watts, by the effective radiating area of the sound head (e.g., 20 watts/10 cm2 sound head = 2.0 w/cm2 SAI).
See also: intensity