Module: ISO_1996::Withdrawn::Part_1_2003

Includes:
Constants
Defined in:
lib/iso_1996/withdrawn/part_1_2003.rb

Overview

ISO 1996-1:2003 Basic Quantities and Assessment Procedures

Module implementing calculations defined in ISO 1996-1:2003: “Acoustics - Description, measurement and assessment of environmental noise - Part 1: Basic quantities and assessment procedures”

Author

Maciej Ciemborowicz

Date

July 11, 2025

Defined Under Namespace

Modules: Constants

Constant Summary

Constants included from Constants

Constants::REFERENCE_SOUND_PRESSURE, Constants::REFERENCE_TIME

Class Method Summary collapse

Class Method Details

.a_weighted_sound_pressure_level(p_a, measurement_time: 1.0) ⇒ Float

Calculate A-weighted sound pressure level (L_A) as defined in Section 3.2

L_A = 10 * log10( (1/T) * ∫(p_A²(t)/p₀²) dt ) dB

Parameters:

  • p_a (Float) —

    A-weighted sound pressure (Pa)

  • measurement_time (Float) (defaults to: 1.0) —

    Measurement time interval (seconds)

Returns:

  • (Float) —

    A-weighted sound pressure level in dB



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# File 'lib/iso_1996/withdrawn/part_1_2003.rb', line 59

def self.a_weighted_sound_pressure_level(p_a, measurement_time: 1.0)
  10 * Math.log10((1.0 / measurement_time) * (p_a ** 2) / (Constants::REFERENCE_SOUND_PRESSURE ** 2))
end

.equivalent_continuous_sound_level(levels, measurement_time) ⇒ Float

Calculate equivalent continuous sound level (L_Aeq,T) as defined in Section 3.7

L_Aeq,T = 10 * log10( (1/T) * Σ(10^(0.1*L_i)) ) dB

Example:

levels = [65.0, 67.0, 63.0]
Basic.equivalent_continuous_sound_level(levels, 3.0) # => ~65.1 dB

Parameters:

  • levels (Array<Float>) —

    Array of sound pressure levels (dB)

  • measurement_time (Float) —

    Total measurement time (seconds)

Returns:

  • (Float) —

    Equivalent continuous sound level in dB

Raises:

  • (ArgumentError) 


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# File 'lib/iso_1996/withdrawn/part_1_2003.rb', line 88

def self.equivalent_continuous_sound_level(levels, measurement_time)
  raise ArgumentError, "Measurement time must be positive" if measurement_time <= 0
  
  return -Float::INFINITY if levels.empty?

  energy_sum = levels.sum { |l| 10 ** (l / 10.0) }
  10 * Math.log10(energy_sum / measurement_time)
end

.peak_sound_pressure_level(p_c_max) ⇒ Float

Calculate C-weighted peak sound pressure level (L_Cpeak) as defined in Section 3.10

L_Cpeak = 20 * log10(p_Cmax / p₀) dB

Parameters:

  • p_c_max (Float) —

    Maximum C-weighted sound pressure (Pa)

Returns:

  • (Float) —

    C-weighted peak sound pressure level in dB



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# File 'lib/iso_1996/withdrawn/part_1_2003.rb', line 105

def self.peak_sound_pressure_level(p_c_max)
  20 * Math.log10(p_c_max / Constants::REFERENCE_SOUND_PRESSURE)
end

.sound_exposure_level(p_a) ⇒ Float

Calculate sound exposure level (L_AE) as defined in Section 3.9

L_AE = 10 * log10( (1/t₀) * ∫(p_A²(t)/p₀²) dt ) dB

Parameters:

  • p_a (Float) —

    A-weighted sound pressure (Pa)

Returns:

  • (Float) —

    Sound exposure level in dB



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# File 'lib/iso_1996/withdrawn/part_1_2003.rb', line 71

def self.sound_exposure_level(p_a)
  10 * Math.log10((1.0 / Constants::REFERENCE_TIME) * (p_a ** 2) / (Constants::REFERENCE_SOUND_PRESSURE ** 2))
end

.sound_pressure_level(p) ⇒ Float

Calculate sound pressure level (L_p) as defined in Section 3.2

L_p = 10 * log10(p² / p₀²) dB

Example:

Basic.sound_pressure_level(0.1) # => 74.0 dB

Parameters:

  • p (Float) —

    Root-mean-square sound pressure (Pa)

Returns:

  • (Float) —

    Sound pressure level in dB



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# File 'lib/iso_1996/withdrawn/part_1_2003.rb', line 46

def self.sound_pressure_level(p)
  10 * Math.log10((p ** 2) / (Constants::REFERENCE_SOUND_PRESSURE ** 2))
end