diff --git a/src/kinetics/Kinetics.cpp b/src/kinetics/Kinetics.cpp
index 55c55ba16..644519146 100644
--- a/src/kinetics/Kinetics.cpp
+++ b/src/kinetics/Kinetics.cpp
@@ -104,12 +104,12 @@ std::pair<size_t, size_t> Kinetics::checkDuplicates(bool throw_err) const
 
         // Compare this reaction to others with similar participants
         vector<size_t>& related = participants[key];
-        for (size_t m = 0; m < related.size(); m++) {
-            Reaction& other = *m_reactions[related[m]];
+        for (size_t m : related) {
+            Reaction& other = *m_reactions[m];
             if (R.duplicate && other.duplicate) {
                 // marked duplicates
                 unmatched_duplicates.erase(i);
-                unmatched_duplicates.erase(related[m]);
+                unmatched_duplicates.erase(m);
                 continue;
             } else if (R.reaction_type != other.reaction_type) {
                 continue; // different reaction types
diff --git a/test/data/duplicate-reactions.cti b/test/data/duplicate-reactions.cti
index 4774a74b2..34d00ab63 100644
--- a/test/data/duplicate-reactions.cti
+++ b/test/data/duplicate-reactions.cti
@@ -21,6 +21,7 @@ make_gas('J', ['C-1', 'F-1', 'I-1']) # unmatched duplicate
 kf = [1e10, 0, 100]
 
 # Forward multiple (not allowed)
+reaction('O + 2 H <=> H2O', kf, id='A-0') # random other reaction
 reaction('O + H2 <=> H + OH', kf, id='A-1')
 reaction('2 O + 2 H2 <=> 2 H + 2 OH', kf, id='A-2')
 
@@ -33,6 +34,7 @@ reaction('H + O2 + AR <=> HO2 + AR', kf, id='C-1')
 reaction('HO2 + AR <=> H + O2 + AR', kf, id='C-2')
 
 # Opposite direction #3 (not allowed)
+reaction('O + 2 H <=> H2O', kf, id='D-0') # random other reaction
 reaction('H + O2 + AR <=> HO2 + AR', kf, id='D-1')
 reaction('HO2 + AR => H + O2 + AR', kf, id='D-2')