diff --git a/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/ConstantRateDevolatilisation/ConstantRateDevolatilisation.C b/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/ConstantRateDevolatilisation/ConstantRateDevolatilisation.C
index 6333e8e65c..7ccb59edb3 100644
--- a/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/ConstantRateDevolatilisation/ConstantRateDevolatilisation.C
+++ b/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/ConstantRateDevolatilisation/ConstantRateDevolatilisation.C
@@ -114,7 +114,7 @@ void Foam::ConstantRateDevolatilisation<CloudType>::calculate
     forAll(volatileData_, i)
     {
         const label id = volatileToGasMap_[i];
-        const scalar massVolatile0 = mass0*YVolatile0_[id];
+        const scalar massVolatile0 = mass0*YVolatile0_[i];
         const scalar massVolatile = mass*YGasEff[id];
 
         // Combustion allowed once all volatile components evolved
diff --git a/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/SingleKineticRateDevolatilisation/SingleKineticRateDevolatilisation.C b/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/SingleKineticRateDevolatilisation/SingleKineticRateDevolatilisation.C
index 388e8c2fa0..5b39e70e59 100644
--- a/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/SingleKineticRateDevolatilisation/SingleKineticRateDevolatilisation.C
+++ b/src/lagrangian/intermediate/submodels/ReactingMultiphase/DevolatilisationModel/SingleKineticRateDevolatilisation/SingleKineticRateDevolatilisation.C
@@ -117,7 +117,7 @@ void Foam::SingleKineticRateDevolatilisation<CloudType>::calculate
     forAll(volatileData_, i)
     {
         const label id = volatileToGasMap_[i];
-        const scalar massVolatile0 = mass0*YVolatile0_[id];
+        const scalar massVolatile0 = mass0*YVolatile0_[i];
         const scalar massVolatile = mass*YGasEff[id];
 
         // Combustion allowed once all volatile components evolved