The human ear’s response to sound level is roughly logarithmic (based on powers of 10), and the dB scale reflects that fact. An increase of 3dB doubles the sound intensity but a 10dB increase is required before a sound is perceived to be twice as loud.
Therefore a small increase in decibels represents a large increase in intensity. For example - 10dB is 10 times more intense than 1dB, while 20dB is 100 times more intense than 1dB. The sound intensity multiplies by 10 with every 10dB increase. Following is a list of dB readings from various sources to act as a non-scientific point of reference:
- 130dB - Jack Hammer (at 5ft)
- 120dB - Rock Concert / Pain threshold
- 110dB - Riveter or a Heavy Truck at 50ft
- 90dB - Heavy Traffic (at 5ft)
- 70dB - Department Store or a Noisy Office
- 50dB - Light Traffic 30dB - Quiet Auditorium
- 20dB - Faint Whisper (at 5ft)
- 10dB - Soundproof room / anechoic chamber
Orion fan noise level is measured in accordance with DIM 45635 standards in an anechoic chamber with the microphone positioned 1 meter from the air intake.
See also:
Source with further information - Orion Fans Technical Terms
DigiKey Fans & Accessories Selection
What makes a Fan noisy
Fan Bearing Types
Fan Bearings & Longevity
Differences between sleeve and ball bearings on fans
CUI Devices omniCOOL™ C, CF, V Series Fan Comparison & Life Expectancy