diff --git a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C
index b7e16296222255b1aebd2949b01b5122a10f8b2f..744ce0d2befe0e57be6ee1f2f3015cf00cd759a0 100644
--- a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C
+++ b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2015-2020 OpenCFD Ltd.
+    Copyright (C) 2015-2021 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -141,7 +141,7 @@ namespace Foam
 {
     tmp<scalarField> safeLog10(const scalarField& fld)
     {
-        auto tresult = tmp<scalarField>::New(fld.size(), Zero);
+        auto tresult = tmp<scalarField>::New(fld.size(), -GREAT);
         auto& result = tresult.ref();
 
         forAll(result, i)
@@ -594,6 +594,7 @@ Foam::noiseModel::noiseModel(const dictionary& dict, const bool readFields)
     windowModelPtr_(),
     graphFormat_("raw"),
     SPLweighting_(weightingType::none),
+    dBRef_(2e-5),
     minPressure_(-0.5*VGREAT),
     maxPressure_(0.5*VGREAT),
     outputPrefix_(),
@@ -663,6 +664,11 @@ bool Foam::noiseModel::read(const dictionary& dict)
 
     Info<< "    Weighting: " << weightingTypeNames_[SPLweighting_] << endl;
 
+    if (dict.readIfPresent("dBRef", dBRef_))
+    {
+        Info<< "    Reference for dB calculation: " << dBRef_ << endl;
+    }
+
     Info<< "    Write options:" << endl;
     dictionary optDict(dict.subOrEmptyDict("writeOptions"));
     readWriteOption(optDict, "writePrmsf", writePrmsf_);
@@ -708,7 +714,7 @@ Foam::tmp<Foam::scalarField> Foam::noiseModel::PSD
     const scalarField& PSDf
 ) const
 {
-    return 10*safeLog10(PSDf/sqr(2e-5));
+    return 10*safeLog10(PSDf/sqr(dBRef_));
 }
 
 
@@ -718,7 +724,7 @@ Foam::tmp<Foam::scalarField> Foam::noiseModel::SPL
     const scalar f
 ) const
 {
-    tmp<scalarField> tspl(10*safeLog10(Prms2/sqr(2e-5)));
+    tmp<scalarField> tspl(10*safeLog10(Prms2/sqr(dBRef_)));
     scalarField& spl = tspl.ref();
 
     switch (SPLweighting_)
@@ -765,7 +771,7 @@ Foam::tmp<Foam::scalarField> Foam::noiseModel::SPL
     const scalarField& f
 ) const
 {
-    tmp<scalarField> tspl(10*safeLog10(Prms2/sqr(2e-5)));
+    tmp<scalarField> tspl(10*safeLog10(Prms2/sqr(dBRef_)));
     scalarField& spl = tspl.ref();
 
     switch (SPLweighting_)
diff --git a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H
index af26b9ba953d85bbd95d58cb7e0903a730b10f3e..254373cc73c20ebfe3ff5ebd3d41ff1cfb511a12 100644
--- a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H
+++ b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2015-2020 OpenCFD Ltd.
+    Copyright (C) 2015-2021 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -63,6 +63,7 @@ Description
         startTime    | Start time                    | no        | 0
         outputPrefix | Prefix applied to output files| no        | ''
         SPLweighting | Weighting: dBA, dBB, dBC, DBD | no        | none
+        dBRef        | Reference for dB calculation  | no        | 2e-5
         graphFormat  | Graph format                  | no        | raw
         writePrmsf   | Write Prmsf data              | no        | yes
         writeSPL     | Write SPL data                | no        | yes
@@ -178,6 +179,9 @@ protected:
         //- Weighting
         weightingType SPLweighting_;
 
+        //- Reference for dB calculation, default = 2e-5
+        scalar dBRef_;
+
 
         // Data validation