diff --git a/GeoLib/Surface.h b/GeoLib/Surface.h
index c7d2933398b89e6b59603d07046631f26fecb38a..ac6460ac782f55f5bc38284609529743a9575e07 100644
--- a/GeoLib/Surface.h
+++ b/GeoLib/Surface.h
@@ -35,7 +35,7 @@ class SurfaceGrid;
 class Surface final : public GeoObject
 {
 public:
-    Surface(const std::vector<Point*>& pnt_vec);
+    explicit Surface(const std::vector<Point*>& pnt_vec);
     ~Surface();
 
     /// return a geometry type