20 to 50 decibels is quiet. On CDC's former scale, a ticking watch is about 20 dB, a soft whisper about 30 dB and a refrigerator hum about 40 dB, and normal conversation about 60 dB. CDC listed nothing at exactly 50 dB; it sits between a refrigerator hum and conversation. Sounds at these levels typically don't cause any hearing damage.
Quiet sounds by level
| Level | Sound |
|---|---|
| 10 dB | Normal breathing |
| 20 dB | Ticking watch |
| 30 dB | Soft whisper |
| 40 dB | Refrigerator hum |
| 60 dB | Normal conversation, air conditioner |
Source: CDC National Center for Environmental Health, "What Noises Cause Hearing Loss?" (last reviewed 8 November 2022). CDC has withdrawn the page; these figures come from an Internet Archive copy dated 2 June 2023. The current pages from NIDCD and NIOSH start at normal conversation.
20 decibels
About a ticking watch on CDC's scale. Many phone and laptop microphones may not be able to measure this low, because their own electrical noise can be louder than the sound.
30 decibels
About a soft whisper, according to CDC's former table.
40 decibels
About a refrigerator hum. Ten times the sound energy of 30 dB, because every 10 dB is a factor of ten.
50 decibels
CDC's table has no example at 50 dB. It is 10 dB above a refrigerator hum and 10 dB below normal conversation (60 dB). Rather than borrow a figure from an unofficial list, we suggest measuring the sounds around you.
Are these levels safe?
- CDC's table says sounds at these levels typically don't cause any hearing damage.
- NIDCD: sounds at or below 70 dBA, even after long exposure, are unlikely to cause hearing loss.
- NIOSH and OSHA set no time limits below 80 dBA.
Measuring quiet sounds
Quiet sounds are the hardest to measure with a phone or laptop. The microphone's own noise and the room's background can be louder than the sound you want, and without calibration readings can be off by 10 dB or more. Use the decibel meter in a still room, keep Processing off, and read the L90 for the background level.
Common questions
How loud is 50 decibels?
Quiet. It is 10 dB above a refrigerator hum (40 dB) and 10 dB below normal conversation (60 dB) on CDC's former scale. CDC listed no example at exactly 50 dB.
How loud is 40 decibels?
About a refrigerator hum, according to CDC's former table of everyday sounds.
How loud is 30 decibels?
About a soft whisper, according to CDC's former table.
How loud is 20 decibels?
About a ticking watch, according to CDC's former table.
Can 40 or 50 decibels damage hearing?
No. CDC's table said sounds at these levels typically don't cause any hearing damage, and NIDCD says sounds at or below 70 dBA are unlikely to cause hearing loss even after long exposure.
Last reviewed 14 November 2026 by Sri Murugan Systems. Found a mistake? Tell us.