How loud is 147 dB?

How loud is 147 dB?

147 decibels is dangerous. 147 dB sounds about 415.9 times as loud as normal conversation (60 dB), and it carries 5.01e+08 times the sound energy. Typical sounds around this level: .22 caliber rifle, jet engine at takeoff, loudest stadium crowd.

Decibels are logarithmic: every +10 dB means ten times more sound intensity but is heard as only about twice as loud, and every +6 dB doubles the sound pressure. That is why a few decibels can make a big difference.

Is 147 dB dangerous?

Yes, with enough exposure. NIOSH recommends no more than less than a second per day at 147 dBA (US law, via OSHA, allows 11 seconds). Hearing damage from noise is cumulative and permanent, so use earplugs or earmuffs, increase distance or reduce exposure time.

Impulse noise and the limits of sound

At 140 dB and above even a single exposure – a gunshot, an explosion, fireworks at close range – can cause immediate, permanent hearing damage. NIOSH sets 140 dB as the ceiling for unprotected impulse noise.

194 dB is the theoretical maximum for an undistorted sound wave in air at sea level: the pressure swings between zero (a vacuum) and twice atmospheric pressure. Beyond that, sound becomes a shock wave.