diff --git a/testApp/chemFoam.C b/testApp/chemFoam.C
index b9b2470..a612718 100644
--- a/testApp/chemFoam.C
+++ b/testApp/chemFoam.C
@@ -47,18 +47,6 @@ Description
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
-const scalar relTol = 10.0 / 100.;
-
-inline scalar relError (scalar x, scalar x0)
-{
-    return (x - x0) / x0;
-}
-
-inline bool exceedTolerence (scalar rError)
-{
-    return rError > relTol || rError < -relTol;
-}
-
 class LogWriter
 {
 
@@ -68,14 +56,27 @@ class LogWriter
 
     label testCount_;
 
+    scalar relTol_;
+
+    scalar relError (scalar x, scalar x0)
+    {
+        return (x - x0) / x0;
+    }
+
+    bool exceedTolerence (scalar rError)
+    {
+        return rError > relTol_ || rError < -relTol_;
+    }
+
 
     public:
 
-    LogWriter ( OFstream &post )
+    LogWriter ( OFstream &post , scalar relTol=(10.0/100.) )
         :
             post_(post),
             errorCount_(0),
-            testCount_(0)
+            testCount_(0),
+            relTol_(relTol)
     {}
 
     label numErrors() {return errorCount_;}
@@ -110,6 +111,13 @@ int main(int argc, char *argv[])
 {
     argList::noParallel();
 
+    argList::addOption
+        (
+         "relTol",
+         "relTol",
+         "Relative tolerence between Cantera and OpenFOAM calculated values"
+        );
+
     #define CREATE_MESH createSingleCellMesh.H
     #define NO_CONTROL
     #include "postProcess.H"
@@ -123,7 +131,9 @@ int main(int argc, char *argv[])
 
     // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
-    LogWriter logWriter (post);
+    scalar relTol = args.optionLookupOrDefault("relTol", 0.1);
+
+    LogWriter logWriter (post, relTol);
 
     Info<< "\nCreate Cantera object\n" << endl;