ISO 80000-8
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ISO 80000-8:2007 is an ISO standard entitled Quantities and units – Part 8: Acoustics, which supersedes ISO 31-7.[1] It is a part of the group of standards called ISO/IEC 80000. The standard specifies names, symbols for quantities and units of acoustics and provides definitions for these quantities and units.
Contents
Contents list[edit]
The standard is divided into the following chapters:
- Foreword
- Introduction
- Scope
- Normative references
- Names, symbols and definitions
Examples[edit]
The standard includes definitions of sound pressure, sound power and sound exposure, and their corresponding levels: sound pressure level, sound power level and sound exposure level. For example
- period duration (symbol T): duration of one cycle of a periodic phenomenon
- frequency (symbol f): f = 1/T
- logarithmic frequency interval (symbol G): G = lb(f2/f1)
- angular frequency (symbol ω): ω = 2πf
- wavelength (symbol λ): for a sinusoidal wave and in a direction perpendicular to the wavefront, distance between two successive points where at a given instant the phase ... differs by 2 π
- wavenumber (symbol σ): σ = 1/λ
- angular wavenumber (symbol k): k = ω/c
- density (symbol ρ): ρ = m/V
- static pressure (symbol ps): pressure that would exist in the absence of sound waves
- sound pressure (symbol p): difference between instantaneous total pressure and static pressure
- sound particle displacement (symbol δ): instantaneous displacement of a particle in a medium from what would be its position in the absence of sound waves
- sound particle velocity (symbol v,u): v = dδ/dt
- sound particle acceleration (symbol a): a = dv/dt
- sound volume velocity (symbol q): surface integral of the normal component of the sound particle velocity ... over the cross-section (through which the sound propagates)
- phase speed of sound (symbol c): c = ω/k
- group speed of sound (symbol cg): cg = dω/dk
- sound energy density (symbol w): time-averaged sound energy in a given volume divided by that volume
- sound power (symbol P, Pa): through a surface, product of the sound pressure ... and the component of the particle velocity ... at a point on the surface in the direction normal to the surface, integrated over that surface
- sound intensity (symbol i): i = p.v
- time-averaged sound intensity (symbol I):
- sound exposure (symbol E):
- characteristic impedance of a medium (symbol Zc): at a point in a non-dissipative medium and for a plane progressive wave, the quotient of the sound pressure ... by the component of the sound particle velocity ... in the direction of the wave propagation
- acoustic impedance (symbol Za): at a surface, the complex quotient of the average sound pressure ... over that surface by the sound volume flow rate ... through that surface
- mechanical surface impedance (symbol Zm): at a surface, the complex quotient of the total force on the surface by the component of the average sound particle velocity ... at the surface in the direction of the force
- sound pressure level (symbol Lp):
- sound power level (symbol LW):
- sound exposure level (symbol LE):
- attenuation coefficient (symbol α):
- phase coefficient (symbol β):
- propagation coefficient (symbol γ):
- dissipation factor for sound power (symbol δ, ψ):
- reflection factor for sound power (symbol r):
- transmission factor for sound power (symbol τ):
- absorption factor for sound power (symbol α):
- sound reduction index (symbol R):
- equivalent absorption area of a surface or object (symbol A):
- reverberation time (symbol Tn):
See also[edit]
- ISO 80000-1 General
- ISO 80000-2 Mathematical signs and symbols to be used in the natural sciences and technology
- ISO 80000-3 Space and time
- ISO 80000-4 Mechanics
- ISO 80000-5 Thermodynamics
- ISO 80000-6 Electromagnetism
- ISO 80000-7 Light
- ISO 80000-9 Physical chemistry and molecular physics
- ISO 80000-10 Atomic and nuclear physics
- ISO 80000-11 Characteristic numbers
- ISO 80000-12 Solid state physics
- IEC 80000-13 Information science and technology
- IEC 80000-14 Telebiometrics related to human physiology
References[edit]
- ^ "ISO 80000-8:2007". International Organization for Standardization. Retrieved 21 July 2013.
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