Noise - EPA Protective Levels
According to the Environmental Protection Agency - EPA - the Day-Night Sound Levels - Ldn - and the Equivalent Sound Level - Leq - should not exceed certain limits to protect public health and welfare.
Values that should not be exceeded:
| Effect | Level | Area |
|---|---|---|
| Hearing | Leq(24) < 70 dBA | All areas |
| Outdoor activity interference and annoyance | Leq < 55 dBA | Outdoors in residential areas and farms where people spend varying amounts of time in which quiet is a basis for use |
| Outdoor activity interference and annoyance | Leq(24) < 55 dBA | Outdoor areas where people spend limited time such as school yards playgrounds, etc. |
| Indoor activity interference and annoyance | Leq < 45 dBA | Indoor residential areas |
| Indoor activity interference and annoyance | Leq(24) < 45 dBA | Indoor areas with human activities such as schools, etc. |
- Outdoor yearly Ldn levels protect public health and welfare if they do not exceed 55 dB in sensitive areas as residences, schools, hospitals, etc.
- Inside buildings yearly Ldn levels protect public health and welfare if they do not exceed 45 dB.
Note! To protect against hearing damage, one's 24-hour noise exposure at the ear should not exceed 70 dB.
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