diff --git a/src/OpenFOAM/containers/LinkedLists/accessTypes/LList/LList.H b/src/OpenFOAM/containers/LinkedLists/accessTypes/LList/LList.H
index eefabca329..f16cf03d14 100644
--- a/src/OpenFOAM/containers/LinkedLists/accessTypes/LList/LList.H
+++ b/src/OpenFOAM/containers/LinkedLists/accessTypes/LList/LList.H
@@ -110,13 +110,13 @@ public:
         {}
 
         //- Construct given initial T
-        LList(T a)
+        explicit LList(T a)
         :
             LListBase(new link(a))
         {}
 
         //- Construct from Istream
-        LList(Istream&);
+        explicit LList(Istream&);
 
         //- Construct as copy
         LList(const LList<LListBase, T>&);