diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h
index c1e827c33fc..14504b02c06 100644
--- a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h
@@ -1031,10 +1031,13 @@ bool is_cells_set_manifold(const C3t3&,
   return true;
 }
 
-template<typename C3t3, typename CellSelector, typename Visitor>
+template<typename C3t3,
+         typename Sizing,
+         typename CellSelector,
+         typename Visitor>
 typename C3t3::Vertex_handle collapse_edge(typename C3t3::Edge& edge,
     C3t3& c3t3,
-    const typename C3t3::Triangulation::Geom_traits::FT& sqhigh,
+    const Sizing& sizing,
     const bool /* protect_boundaries */,
     CellSelector cell_selector,
     Visitor& )
@@ -1106,6 +1109,8 @@ typename C3t3::Vertex_handle collapse_edge(typename C3t3::Edge& edge,
     }
   }
 
+  const auto sqhigh = squared_upper_size_bound(edge, sizing, c3t3.triangulation());
+
   if (are_edge_lengths_valid(edge, c3t3, new_pos, sqhigh, cell_selector/*, adaptive = false*/)
     && collapse_preserves_surface_star(edge, c3t3, new_pos, cell_selector))
   {
@@ -1205,17 +1210,9 @@ void collapse_short_edges(C3T3& c3t3,
   typedef typename Boost_bimap::value_type            short_edge;
 
   T3& tr = c3t3.triangulation();
-  typename Gt::Compute_squared_length_3 sql
-    = tr.geom_traits().compute_squared_length_3_object();
-
-  const FT target_edge_length = sizing(CGAL::ORIGIN, 0, 0);
-  const FT low = FT(4) / FT(5) * target_edge_length;
-  const FT high = FT(4) / FT(3) * target_edge_length;
-  const FT sq_low = low*low;
-  const FT sq_high = high*high;
 
 #ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
-  std::cout << "Collapse short edges (" << low << ", " << high << ")...";
+  std::cout << "Collapse short edges...";
   std::cout.flush();
   std::size_t nb_collapses = 0;
 #endif
@@ -1227,9 +1224,9 @@ void collapse_short_edges(C3T3& c3t3,
     if (!can_be_collapsed(e, c3t3, protect_boundaries, cell_selector))
       continue;
 
-    FT sqlen = sql(tr.segment(e));
-    if (sqlen < sq_low)
-      short_edges.insert(short_edge(make_vertex_pair<T3>(e), sqlen));
+    const auto sqlen = is_too_short(e, sizing, tr);
+    if(sqlen != std::nullopt)
+      short_edges.insert(short_edge(make_vertex_pair<T3>(e), sqlen.value()));
   }
 
 #ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
@@ -1254,12 +1251,13 @@ void collapse_short_edges(C3T3& c3t3,
     std::cout << nb_collapses << " collapses)";
     std::cout.flush();
 #endif
+
     Cell_handle cell;
     int i1, i2;
     if ( tr.tds().is_vertex(e.first)
          && tr.tds().is_vertex(e.second)
          && tr.tds().is_edge(e.first, e.second, cell, i1, i2)
-         && tr.segment(Edge(cell, i1, i2)).squared_length() < sq_low)
+         && is_too_short(Edge(cell, i1, i2), sizing, tr))
     {
 #ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
       const typename T3::Point p1 = e.first->point();
@@ -1276,7 +1274,7 @@ void collapse_short_edges(C3T3& c3t3,
         continue;
       }
 
-      Vertex_handle vh = collapse_edge(edge, c3t3, sq_high,
+      Vertex_handle vh = collapse_edge(edge, c3t3, sizing,
                                        protect_boundaries, cell_selector,
                                        visitor);
       if (vh != Vertex_handle())
@@ -1289,9 +1287,9 @@ void collapse_short_edges(C3T3& c3t3,
           if (!can_be_collapsed(eshort, c3t3, protect_boundaries, cell_selector))
             continue;
 
-          const FT sqlen = sql(tr.segment(eshort));
-          if (sqlen < sq_low)
-            short_edges.insert(short_edge(make_vertex_pair<T3>(eshort), sqlen));
+          const auto sqlen = is_too_short(eshort, sizing, tr);
+          if (sqlen != std::nullopt)
+            short_edges.insert(short_edge(make_vertex_pair<T3>(eshort), sqlen.value()));
         }
 
         //debug::dump_c3t3(c3t3, "dump_after_collapse");
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h
index 4467c713c8b..57f17b540f5 100644
--- a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h
@@ -26,6 +26,7 @@
 #include <unordered_map>
 #include <functional>
 #include <utility>
+#include <optional>
 
 namespace CGAL
 {
@@ -234,6 +235,8 @@ bool can_be_split(const typename C3T3::Edge& e,
   }
 }
 
+
+
 template<typename C3T3,
          typename Sizing,
          typename CellSelector,
@@ -253,19 +256,15 @@ void split_long_edges(C3T3& c3t3,
   typedef typename T3::Geom_traits     Gt;
   typedef typename T3::Geom_traits::FT FT;
   typedef boost::bimap<
-  boost::bimaps::set_of<Edge_vv>,
+        boost::bimaps::set_of<Edge_vv>,
         boost::bimaps::multiset_of<FT, std::greater<FT> > >  Boost_bimap;
   typedef typename Boost_bimap::value_type               long_edge;
 
-  const FT target_edge_length = sizing(CGAL::ORIGIN, 0, 0);
-  const FT high = FT(4) / FT(3) * target_edge_length;
-
 #ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
-  std::cout << "Split long edges (" << high << ")...";
+  std::cout << "Split long edges...";
   std::cout.flush();
   std::size_t nb_splits = 0;
 #endif
-  const FT sq_high = high*high;
 
   //collect long edges
   T3& tr = c3t3.triangulation();
@@ -275,11 +274,9 @@ void split_long_edges(C3T3& c3t3,
     if (!can_be_split(e, c3t3, protect_boundaries, cell_selector))
       continue;
 
-    typename Gt::Compute_squared_length_3 sql
-      = tr.geom_traits().compute_squared_length_3_object();
-    FT sqlen = sql(tr.segment(e));
-    if (sqlen > sq_high)
-      long_edges.insert(long_edge(make_vertex_pair<T3>(e), sqlen));
+    const std::optional<FT> sqlen = is_too_long<T3>(e, sizing, tr);
+    if(sqlen != std::nullopt)
+      long_edges.insert(long_edge(make_vertex_pair<T3>(e), sqlen.value()));
   }
 
 #ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h
index d6ccc1fe834..fb0bce2a041 100644
--- a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h
@@ -174,16 +174,6 @@ public:
     return m_c3t3_pbackup != NULL;
   }
 
-  bool is_too_long(const Edge& e) const
-  {
-    const FT target_edge_length
-      = m_sizing(CGAL::midpoint(tr().segment(e)),
-                 0,
-                 0);
-    const FT emax = FT(4)/FT(3) * target_edge_length;
-    return tr().segment(e).squared_length() > CGAL::square(emax * emax);
-  }
-
   bool is_too_short(const Edge& e) const
   {
     const FT target_edge_length
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h
index f566ab1890f..0fbbe30850f 100644
--- a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h
@@ -31,6 +31,8 @@
 #include <boost/container/flat_set.hpp>
 #include <boost/container/small_vector.hpp>
 
+#include <optional>
+
 namespace CGAL
 {
 namespace Tetrahedral_remeshing
@@ -982,6 +984,74 @@ bool topology_test(const typename C3t3::Edge& edge,
   return true;
 }
 
+template<typename Tr, typename Sizing>
+typename Tr::Geom_traits::FT
+squared_upper_size_bound(const typename Tr::Edge& e,
+                         const Sizing& sizing,
+                         const Tr& tr)
+{
+  using FT = typename Tr::Geom_traits::FT;
+
+  const FT target_edge_length
+    = sizing(CGAL::midpoint(tr.segment(e)),
+             0,
+             0);
+  const FT emax = FT(4) / FT(3) * target_edge_length;
+  return CGAL::square(emax);
+}
+
+template<typename Tr, typename Sizing>
+typename Tr::Geom_traits::FT
+squared_lower_size_bound(const typename Tr::Edge& e,
+                         const Sizing& sizing,
+                         const Tr& tr)
+{
+  using FT = typename Tr::Geom_traits::FT;
+
+  const FT target_edge_length
+    = sizing(CGAL::midpoint(tr.segment(e)),
+             0,
+             0);
+  const FT emin = FT(4) / FT(5) * target_edge_length;
+  return CGAL::square(emin);
+}
+
+template<typename Tr, typename Sizing>
+std::optional<typename Tr::Geom_traits::FT>
+is_too_long(const typename Tr::Edge& e,
+            const Sizing& sizing,
+            const Tr& tr)
+{
+  using FT = typename Tr::Geom_traits::FT;
+  auto sql = tr.geom_traits().compute_squared_length_3_object();
+
+  const FT sq_max = squared_upper_size_bound(e, sizing, tr);
+  const FT sqlen = sql(tr.segment(e));
+
+  if (sqlen > sq_max)
+    return sqlen;
+  else
+    return std::nullopt;
+}
+
+template<typename Tr, typename Sizing>
+std::optional<typename Tr::Geom_traits::FT>
+is_too_short(const typename Tr::Edge& e,
+             const Sizing& sizing,
+             const Tr& tr)
+{
+  using FT = typename Tr::Geom_traits::FT;
+  auto sql = tr.geom_traits().compute_squared_length_3_object();
+
+  const FT sq_min = squared_lower_size_bound(e, sizing, tr);
+  const FT sqlen = sql(tr.segment(e));
+
+  if (sqlen < sq_min)
+    return sqlen;
+  else
+    return std::nullopt;
+}
+
 template<typename C3t3>
 Subdomain_relation compare_subdomains(const typename C3t3::Vertex_handle v0,
                                       const typename C3t3::Vertex_handle v1,