diff --git a/src/server/BreCal/validators/validation_rule_functions.py b/src/server/BreCal/validators/validation_rule_functions.py
index a8138ab..478a7cf 100644
--- a/src/server/BreCal/validators/validation_rule_functions.py
+++ b/src/server/BreCal/validators/validation_rule_functions.py
@@ -268,7 +268,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.eta_berth'.
         """
         # check, if the header is filled in (agency & MOORING)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.MOORING.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.MOORING.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -298,7 +298,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.etd_berth'.
         """
         # check, if the header is filled in (agency & MOORING)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.MOORING.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.MOORING.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -328,7 +328,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.eta_berth'.
         """
         # check, if the header is filled in (agency & PORT_ADMINISTRATION)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.PORT_ADMINISTRATION.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.PORT_ADMINISTRATION.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -358,7 +358,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.etd_berth'.
         """
         # check, if the header is filled in (agency & PORT_ADMINISTRATION)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.PORT_ADMINISTRATION.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.PORT_ADMINISTRATION.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -388,7 +388,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.eta_berth'.
         """
         # check, if the header is filled in (agency & PILOT)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.PILOT.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.PILOT.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -418,7 +418,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.etd_berth'.
         """
         # check, if the header is filled in (agency & PILOT)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.PILOT.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.PILOT.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -448,7 +448,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.eta_berth'.
         """
         # check, if the header is filled in (agency & TUG)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.TUG.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.TUG.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -478,7 +478,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.etd_berth'.
         """
         # check, if the header is filled in (agency & TUG)
-        if len(df_times.loc[df_times["participant_type"].isin([ParticipantType.AGENCY.value, ParticipantType.TUG.value])]) != 2:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.TUG.value]) != 1):
             return self.get_no_violation_default_output()
         
         # preparation: obtain the correct times of the participant, define the query time and the key time
@@ -508,10 +508,7 @@ class ValidationRuleFunctions(ValidationRuleBaseFunctions):
             - Measures the difference between 'now' and 'times_agency.eta_berth'.
         """
         # check, if the header is filled in (agency & terminal)
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1:
-            return self.get_no_violation_default_output() # rule not applicable
-
-        if len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) != 1:
+        if (len(df_times.loc[df_times["participant_type"]==ParticipantType.AGENCY.value]) != 1) or (len(df_times.loc[df_times["participant_type"]==ParticipantType.TERMINAL.value]) != 1):
             return self.get_no_violation_default_output() # rule not applicable
         
         # preparation: obtain the correct times of the participant, define the query time and the key time