With regard to stadium noise a reader writes,
Noise exposure, like hazardous chemical exposure, is tricky to measure. The relevant concept is DOSE. Dose is a factor of volume (or concentration) and duration. Most high noise exposures are short duration. Think gun shots or other impact noises. Not a real problem unless, for ex, you’re a competitive skeet shooter or pile driver. Of greater import are continuous high volume noises like those experienced by musicians and concert goers. A big deal, especially for higher frequency noise.
Right. Energy / volume1, basically – with enough volume, who cares how much energy? Although there’s the trickier question of point of origin of the energy, and in a stadium there will be multiple sources. Time to call in an acoustic engineer.
1Odd how ‘volume’ can mean 3 dimensional space or audio level, and that it is confusing in this context; I mean it in the former sense in this case.