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Noise - EPA Protective Levels

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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:

Noise - EPA Protective Levels
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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