Edit: I believe the best foam earplugs are usually around -32 dB. There was recently a lawsuit against a foam earplug manufacturer where the plugs were well bel

Edit: I believe the best foam earplugs are usually around -32 dB. There was recently a lawsuit against a foam earplug manufacturer where the plugs were well below their stated protection level. Maybe I used them at some point, who could say! From what I've read, pressurized air is one of the worst offenders for causing damage, such as when a pressure valve is released and it suddenly vents. Related anecdote, while my wife was pregnant with our son I was using a small air tank and a finishing nailer. I didn't need the tank pressurized anymore so I pulled the over-pressure emergency valve and it dumped all the air immediately. So loudly that it made my son jump in the womb and startle my wife twice - once for the sound, once for the kick :)