Noise Environmental - World Health Organization ( BS.8233 )
1980 WHO Criteria it is stated-
- "A level of less than 35 dBA Leq is recommended to preserve the restorative process of sleep".
- "The probability of persons being awakened by internal noise peaks of 40dBA is 10%, rising at 70 dBA to 30%."
Hoe Loud and How Lomg
Noise can permanently damage your hearing is by a single brief exposure to a high noise level.
Example:- A firecracker going off near your ear. At 140 decibels, immediate nerve damage can occur.
Hearing damage can also occur gradually at much lower levels of noise, if there is enough exposure over time.
Example:-
Example:- A firecracker going off near your ear. At 140 decibels, immediate nerve damage can occur.
Hearing damage can also occur gradually at much lower levels of noise, if there is enough exposure over time.
Example:-
- At 91 decibels, your ears can tolerate up to two hours of exposure.
- At 100 decibels, damage can occur with 15 minutes of exposure.
- At 112 decibels, damage can occur with only one minute of exposure.
The risk to your hearing from noise exposure depends on how loud it is and how long you're exposed to it. This noise dose chart shows the acceptable safety limits.
Note:-
For children, the World Health Organization recommends no exposure above 120 dB.
Maximum Recommended Noise Dose for Exposure
Noise Level [dBA] Maximum Exposure Time
85 8 hours
88 4 hours
91 2 hours
94 1 hour
97 30 minutes
100 15 minutes
103 7.5 minutes
106 3.7 minutes
109 112 seconds
112 56 seconds
115 28 seconds
118 14 seconds
121 7 seconds
124 3 seconds
127 1 second
130–140 less than 1 second
85 8 hours
88 4 hours
91 2 hours
94 1 hour
97 30 minutes
100 15 minutes
103 7.5 minutes
106 3.7 minutes
109 112 seconds
112 56 seconds
115 28 seconds
118 14 seconds
121 7 seconds
124 3 seconds
127 1 second
130–140 less than 1 second