diff --git a/env/DAMASK.sh b/env/DAMASK.sh
index 335fb4a6b..c74c447ed 100644
--- a/env/DAMASK.sh
+++ b/env/DAMASK.sh
@@ -55,7 +55,8 @@ if [ ! -z "$PS1" ]; then
     || echo "               ~~> "$(canonicalPath "$PETSC_DIR")
   fi
   [ "x$PETSC_ARCH" != "x" ] && echo "PETSc architecture $PETSC_ARCH"
-  [ "x$OMP_NUM_THREADS" != "x" ] && echo "Multithreading     OMP_NUM_THREADS=$OMP_NUM_THREADS"
+  [ "x$OMP_NUM_THREADS" == "x" ] && export OMP_NUM_THREADS=4
+  echo "Multithreading     OMP_NUM_THREADS=$OMP_NUM_THREADS"
   echo -n "heap  size         "
    [[ "$(ulimit -d)" == "unlimited" ]] \
    && echo "unlimited" \
diff --git a/env/DAMASK.zsh b/env/DAMASK.zsh
index c4c7b705c..5813d110a 100644
--- a/env/DAMASK.zsh
+++ b/env/DAMASK.zsh
@@ -45,7 +45,8 @@ if [ ! -z "$PS1" ]; then
     || echo "               ~~> "$(canonicalPath "$PETSC_DIR")
   fi
   [[ "x$PETSC_ARCH" != "x" ]] && echo "PETSc architecture $PETSC_ARCH"
-  [[ "x$OMP_NUM_THREADS" != "x" ]] && echo "Multithreading     OMP_NUM_THREADS=$OMP_NUM_THREADS"
+  [[ "x$OMP_NUM_THREADS" == "x" ]] && export OMP_NUM_THREADS=4
+  echo "Multithreading     OMP_NUM_THREADS=$OMP_NUM_THREADS"
   echo -n "heap  size         "
    [[ "$(ulimit -d)" == "unlimited" ]] \
    && echo "unlimited" \
diff --git a/python/damask/_grid.py b/python/damask/_grid.py
index 1b58870e4..9e30ba5f9 100644
--- a/python/damask/_grid.py
+++ b/python/damask/_grid.py
@@ -392,7 +392,7 @@ class Grid:
             seeds_p   = seeds
             coords    = grid_filters.coordinates0_point(cells,size).reshape(-1,3)
 
-        pool = mp.Pool(int(os.environ.get('OMP_NUM_THREADS',1)))
+        pool = mp.Pool(int(os.environ.get('OMP_NUM_THREADS',4)))
         result = pool.map_async(partial(Grid._find_closest_seed,seeds_p,weights_p), [coord for coord in coords])
         pool.close()
         pool.join()
@@ -437,7 +437,7 @@ class Grid:
         """
         coords = grid_filters.coordinates0_point(cells,size).reshape(-1,3)
         KDTree = spatial.cKDTree(seeds,boxsize=size) if periodic else spatial.cKDTree(seeds)
-        devNull,material_ = KDTree.query(coords)
+        devNull,material_ = KDTree.query(coords, workers = int(os.environ.get('OMP_NUM_THREADS',4)))
 
         return Grid(material = (material_ if material is None else material[material_]).reshape(cells),
                     size     = size,
diff --git a/python/damask/_result.py b/python/damask/_result.py
index 0520f08f2..8dd915d1b 100644
--- a/python/damask/_result.py
+++ b/python/damask/_result.py
@@ -1179,7 +1179,7 @@ class Result:
 
         """
         chunk_size = 1024**2//8
-        pool = mp.Pool(int(os.environ.get('OMP_NUM_THREADS',1)))
+        pool = mp.Pool(int(os.environ.get('OMP_NUM_THREADS',4)))
         lock = mp.Manager().Lock()
 
         groups = []