Table 3. CENTERFIRE PISTOL DATA
.25 ACP 155.0 dB
.32 LONG 152.4 dB
.32 ACP 153.5 dB
.380 157.7 dB
9mm 159.8 dB
.38 S&W 153.5 dB
.38 Spl 156.3 dB
.357 Magnum 164.3 dB
.41 Magnum 163.2 dB
.44 Spl 155.9 dB
.45 ACP 157.0 dB
.45 COLT 154.7 dB
A typical .22LR meters 150-155 dB.
Continual exposure to any of these will cause permanent hearing loss.
Sound decreases as the square of the distance from the source.
Enclosures or reflecting surfaces will direct sound.