diff --git a/src/Bnd/Bnd_Box.lxx b/src/Bnd/Bnd_Box.lxx
index f42707fa20..edf29b7e57 100644
--- a/src/Bnd/Bnd_Box.lxx
+++ b/src/Bnd/Bnd_Box.lxx
@@ -21,8 +21,8 @@
 inline Standard_Real Bnd_Box::SquareExtent() const 
 {
   if ( IsVoid() ) return 0.;
-  Standard_Real dx = Xmax-Xmin+Gap;
-  Standard_Real dy = Ymax-Ymin+Gap;
-  Standard_Real dz = Zmax-Zmin+Gap;
-  return dx*dx + dy*dy + dz*dz;
+  const Standard_Real aDx = Xmax - Xmin + Gap + Gap;
+  const Standard_Real aDy = Ymax - Ymin + Gap + Gap;
+  const Standard_Real aDz = Zmax - Zmin + Gap + Gap;
+  return aDx*aDx + aDy*aDy + aDz*aDz;
 }
diff --git a/src/Bnd/Bnd_Box2d.lxx b/src/Bnd/Bnd_Box2d.lxx
index 346aac6268..57697d66b0 100644
--- a/src/Bnd/Bnd_Box2d.lxx
+++ b/src/Bnd/Bnd_Box2d.lxx
@@ -238,8 +238,8 @@ inline Standard_Boolean Bnd_Box2d::IsOut (const gp_Trsf2d& T1,
 inline Standard_Real Bnd_Box2d::SquareExtent() const 
 {
   if ( IsVoid() ) return 0.;
-  Standard_Real dx = Xmax-Xmin+Gap;
-  Standard_Real dy = Ymax-Ymin+Gap;
-  return dx*dx + dy*dy;
+  const Standard_Real aDx = Xmax - Xmin + Gap + Gap;
+  const Standard_Real aDy = Ymax - Ymin + Gap + Gap;
+  return aDx*aDx + aDy*aDy;
 }