Railroad

Schall03 (1990)

Calculation:

Emission	Lw = Lm,E + 19.2 + 10 lg (length) - (railway correction) [dB(A)]
Immission	Lr,k = Lw + Di,k + Ds,k + Dl,k + Dbm,k + De,k + Dg,k + Dr2,k - RL + 19.2 [dB(A)]

Parameters:

Lm,E	emission level 25 m perpendicular from the railroad’s axis [dB(A)]
Di,k	level difference due to directivity index (dB)
Ds,k	attenuation due to divergence (dB)
Dl,k	level difference due to atmospheric absorption (dB)
Dbm,k	attenuation due to meteorological and ground (dB)
De,k	level difference due to barriers (dB)
Dg,k	level difference due to foliage (dB)
Dr2,k	level difference due to multiple reflection (dB)

Schall03 (2014)

Calculation:

Emission	Lw = L‘w + 10 lg (length) - (railway correction) [dB(A)]
Immission	Lr = Lw + K0 - Dc - Adiv - Aatm - Agr - Afol - Ahous - Abar - Cmet - RL [dB(A)]

Parameters:

Lw	sound power level per unit length L‘w [dB(A)]
K0	directivity index (dB), = Domega in ISO 9613-2
Dc	directivity correction (dB)
Adiv	attenuation due to divergence (dB)
Aatm	atmospheric absorption index (dB)
Agr	attenuation due to ground absorption (dB)
Afol	attenuation due to foliage (dB)
Ahous	attenuation by buildings (dB)
Abar	attenuation due to screening (dB)
Cmet	meteorological correction for long-term average level (dB)

ONR 305011

Calculation (accord. to ONR 305011:2004-09-01 ONR305011-2004):

Emission	Lw = Lw,eq + 10 lg (length or area) - (railway correction) [dB(A)]
Immission	Lr = Lw - DLphi + DLd + DLa + DLs + DLv + DLb + DLst - RL [dB(A)]

Parameters:

Lw	sound power level Lw,eq [dB(A)]
DLphi	directivity correction (dB)
DLd	attenuation due to divergence (dB)
DLa	atmospheric absorption index (dB)
DLs	attenuation due to screening (dB)
DLv	attenuation due to foliage (dB)
DLb	attenuation due to effects of the ground (dB)
DLst	attenuation due to sound dispersion by buildings (dB)

For calculations accord. to ONR 305011:2009-11-15 ONR305011-2009 see section „Industry, ISO 9613“.

DIN 18005 (1987)

Calculation:

Emission	Lw = Lm,E + 19.2 - Drefl + 10 lg (length or area) + DLk [dB(A)] with DLk railway correction (dB)
Immission	Lr = Lw - DLs - DLz - DLg - RL [dB(A)]

Parameters:

Lw	emission level Lm,E [dB(A)]
DLs	attenuation due to divergence (dB)
DLz	attenuation due to screening (dB)
DLg	attenuation due to buildings and/or foliage (dB)

Nordic Pred. Method 1996

Calculation:

Emission	Lw = Lwo’ + 10 lg (length) - (railway correction) [dB(A)]
Immission	Lr (LA,eq) = Lw + DLd + DLa + DLg + DLs + DLv + DLst - RL [dB(A)]

Parameters:

Lw	reference sound power level Lwo’ per unit length [dB(A)]
DLd	attenuation due to divergence (dB)
DLa	attenuation due to air absorption (dB)
DLg	ground attenuation (dB)
DLs	attenuation due to screening (dB)
DLv	attenuation due to vegetation (dB)
DLst	attenuation due to sound dispersion by buildings (dB)

Semibel

Calculation:

Emission	Lw = Leq,e + MK [dB(A)] with MK model correction (dB)
Immission	Lr = Lw - dS - DR - dPhi - dL - dB - dH - RL [dB(A)]

Parameters:

Leq,e	emission level [dB(A)]
dS	attenuation due to divergence (dB)
DR	attenuation due to directivity (dB)
dPhi	reduction due to aspect angle (dB)
dL	attenuation due to air absorption (dB)
dB	ground attenuation (dB)
dH	attenuation due to screening (dB)

CRN

Calculation:

Emission	Lw = LA25m,18h [dB(A)]
Immission	Lr = Lw + Cdist + Cair + Cgnd + Cball + Cscrn + Cangl + Crefl (Reflect. via Correction.) [dB(A)] Lr = Lw Cdist + Cair + Cgnd + Cball + Cscrn + Cangl - RL (Reflect. via mirror sources) [dB(A)]

Parameters:

LA25m,18h	emission level [dB(A)]
Cdist	distance correction (dB)
Cair	air absorption correction (dB)
Cgnd	ground correction (dB)
Cball	correction for ballasted track (dB)
Cscrn	screening correction (dB)
Cangl	angle of view correction (dB)
Crefl	reflection correction (dB)

SRM II

Calculation:

Emission	LAE = LE + 10 lg (length) - (A-weighting) - (railway correction) [dB(A)]
Immission	LA,eq = LE + DLgu - Dl - Db - Cm - DLsw - DLr - 58.6 [dB(A)]

Parameters:

LE (D/E/N)	emission level [dB(A)]
DLgu	attenuation due to distance (dB)
Dl	air attenuation (dB)
Db	ground attenuation (dB)
Cm	meteorological correction (dB)
DLsw	screening effect (dB)
DLr	attenuation due to reflections (dB)

NMPB-Fer

Calculation:

Emission	Lw,i = L’w,i + 10 lg (length) + R(i) [dB(A)] with R(i) A-weighting in octave band width (dB)
Immission	Lr,i = Lw,i - Adiv - Aatm + Adir - Asol(H/F) - Adif(H/F) - RL [dB(A)]

Parameters:

L‘w	sound power level per unit length in octave bands [dB(A)]
Adiv	attenuation due to divergence (dB)
Aatm	atmospheric absorption index (dB)
Adir	directivity correction (dB)
AsolH	ground attenuation for homogeneous conditions (dB)
AsolF	ground attenuation for favorable conditions (dB)
AdifH	attenuation due to diffraction for homogeneous conditions (dB)
AdifF	attenuation due to diffraction for favorable conditions (dB)

NMPB-Fer-2008

Calculation:

Emission	Lw,i = L‘wi + 10 lg (length) + R(i) [dB(A)] with R(i) A-weighting in third-octave i (dB)
Immission	Lr = Lw + Adiv + Aatm + Asol(H/F) + Adif(H/F) - RL [dB(A)]

Parameters:

Lw	sound power level per unit length LAwi’, in third-octave i [dB(A)]
Adiv	attenuation due to divergence (dB)
Aatm	atmospheric absorption index (dB)
AsolH	ground attenuation for homogeneous conditions (dB)
AsolF	ground attenuation for favorable conditions (dB)
AdifH	attenuation due to diffraction for homogeneous conditions (dB
AdifF	attenuation due to diffraction for favorable conditions (dB)

CNOSSOS-EU

see NMPB-Fer-2008

FTA/FRA

Calculation:

Emission	Lw = Leq,50ft + 10 lg (length) - (railway correction) [dB(A)]
Immission	Lr = Lw,i + Ageo + Aangle + Agr + Ashield - RL [dB(A)] Lw,sum = sum (Lw,i) [dB(A)]

Parameters:

Lw	emission level Leq,50ft (50 ft from infinite long, straight track) [dB(A)]
Ageo	attenuation due to divergence (dB)
Aangle	attenuation due to angle of view (dB)
Agr	ground attenuation (dB)
Ashield	attenuation due to shielding effects (dB)