diff --git a/saqc/funcs/harm_functions.py b/saqc/funcs/harm_functions.py
index 88e1fe533da9292bd5fd314257d3aafa92d826b2..1eff59ebbdb955cd6cc8555399547fd850ad9407 100644
--- a/saqc/funcs/harm_functions.py
+++ b/saqc/funcs/harm_functions.py
@@ -13,42 +13,41 @@ logger = logging.getLogger("SaQC")
 
 
 @register
-def harm_shift2Grid(data, field, flagger, freq, method="nshift", drop_flags=None, empty_intervals_flag=None, **kwargs):
+def harm_shift2Grid(data, field, flagger, freq, method="nshift", drop_flags=None, **kwargs):
 
     data, flagger = proc_fork(data, field, flagger)
     data, flagger = proc_shift(data, field, flagger, freq, method, drop_flags=drop_flags,
-                               empty_intervals_flag=empty_intervals_flag, **kwargs)
+                               empty_intervals_flag=flagger.UNFLAGGED, **kwargs)
     return data, flagger
 
 
 @register
 def harm_aggregate2Grid(
-    data, field, flagger, freq, value_func, flag_func=np.nanmax, method="nagg", drop_flags=None,
-        empty_intervals_flag=None, **kwargs
+    data, field, flagger, freq, value_func, flag_func=np.nanmax, method="nagg", drop_flags=None, **kwargs
 ):
 
     data, flagger = proc_fork(data, field, flagger)
     data, flagger = proc_resample(data, field, flagger, freq, agg_func=value_func, flag_agg_func=flag_func,
-                                  method=method, empty_intervals_flag=empty_intervals_flag, drop_flags=drop_flags,
+                                  method=method, empty_intervals_flag=flagger.UNFLAGGED, drop_flags=drop_flags,
                                   all_na_2_empty=True, **kwargs)
     return data, flagger
 
 
 @register
-def harm_linear2Grid(data, field, flagger, freq, drop_flags=None, empty_intervals_flag=None, **kwargs):
+def harm_linear2Grid(data, field, flagger, freq, drop_flags=None, **kwargs):
     data, flagger = proc_fork(data, field, flagger)
     data, flagger = proc_interpolateGrid(data, field, flagger, freq, 'time',
-                                         drop_flags=drop_flags, empty_intervals_flag=empty_intervals_flag, **kwargs)
+                                         drop_flags=drop_flags, empty_intervals_flag=flagger.UNFLAGGED, **kwargs)
     return data, flagger
 
 
 @register
 def harm_interpolate2Grid(
-    data, field, flagger, freq, method, order=1, drop_flags=None, empty_intervals_flag=None, **kwargs,
+    data, field, flagger, freq, method, order=1, drop_flags=None, **kwargs,
 ):
     data, flagger = proc_fork(data, field, flagger)
     data, flagger = proc_interpolateGrid(data, field, flagger, freq, method=method, inter_order=order,
-                                         drop_flags=drop_flags, empty_intervals_flag=empty_intervals_flag,
+                                         drop_flags=drop_flags, empty_intervals_flag=flagger.UNFLAGGED,
                                          **kwargs)
     return data, flagger