Also both would be “safe” for about 10 shots. More than enough for a single shot. Do you get less dose with a 3db reduction, sure. But the current theory is keep dose low enough and damage doesn’t occur. So there is a difference in the number of “safe” shots between 130 and 127, but it’s pretty much immaterial for a hunter who takes 1-3 shots.
From what I understand about hearing damage is, it depends. Your genetics, ear canal shape, the sound exposure all can change the level at which damage occurs. Even sub 140 can cause damage, just as some people can handle above 140 without damage. Thus the 140 is not a hard limit for instant hearing damage. Also damage may not show up for years as the methods to test for it are not perfect.
