Sound power level measures total radiated acoustic power referenced to 1 picowatt

Evidence

The sound power level is useful for comparing the total acoustic power radiated by objects, for example ones which generate unwanted noises. It has the advantage of not depending on the acoustic context, as we shall see in Chapter 6. Note that, unlike the sound intensity, the sound power has no particular direction. — David Howard, Jamie Angus, coustics and Psychoacoustics, 175

Categorization

• DEFINE: Distinguishes sound power level (context-free, omnidirectional) from sound intensity (point-specific and directional).
• corroborated: 2 independent passages support this claim — David Howard, Jamie Angus, coustics and Psychoacoustics, 175