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Epa Protective Noise Level

Reference data and engineering information about epa protective noise level for acoustics applications.

epaprotectivenoiselevel

Overview

Engineering reference data for Epa Protective Noise Level in acoustics.

Key Formulas

Speed of Sound

c=γRTc = \sqrt{\gamma R T}

Speed of sound in an ideal gas.

Sound Level

L=10log⁡10(I/I0)L = 10 \log_{10}(I/I_0)

Decibel level.

Wavelength

λ=c/f\lambda = c / f

Wavelength = speed / frequency.

Variables

SymbolDescriptionUnit
ccSpeed of soundm/s
LLSound leveldB
λ\lambdaWavelengthm
ffFrequencyHz

Definitions

  • Leq (Equivalent Sound Level): The constant sound level that contains the same sound energy as the actual varying noise over a specified period.
  • Ldn (Day-Night Sound Level): A 24-hour average sound level metric where nighttime levels (10 PM to 7 AM) are increased by 10 dB to account for greater sensitivity during sleep.
  • Leq(24): Specifically denotes the equivalent sound level averaged over a full 24-hour period.
5 rows
EPA Recommended Maximum Noise Levels to protect public health and welfare.
Effect
Level
Area
HearingLeq(24) < 70 dBAAll areas
Outdoor activity interference & annoyanceLeq < 55 dBAOutdoors in residential areas & farms where people spend varying amounts of time in which quiet is a basis for use
Outdoor activity interference & annoyanceLeq(24) < 55 dBAOutdoor areas where people spend limited time such as school yards playgrounds, etc.
Indoor activity interference & annoyanceLeq < 45 dBAIndoor residential areas
Indoor activity interference & annoyanceLeq(24) < 45 dBAIndoor areas with human activities such as schools, etc.

Source: Environmental Protection Agency (EPA)

Note

To protect against hearing damage, the 24-hour noise exposure at the ear (Leq(24)) should not exceed 70 dB. This limit is reflected in the EPA protective level for hearing in the table above.

References

Source: engineeringtoolbox.com