diff --git a/src/primaite/environment/primaite_env.py b/src/primaite/environment/primaite_env.py
index 7608e7db..be4cc434 100644
--- a/src/primaite/environment/primaite_env.py
+++ b/src/primaite/environment/primaite_env.py
@@ -107,6 +107,7 @@ class Primaite(Env):
 
         # Create a dictionary to hold all the green IERs (this will come from an external source)
         self.green_iers: Dict[str, IER] = {}
+        self.green_iers_reference: Dict[str, IER] = {}
 
         # Create a dictionary to hold all the node PoLs (this will come from an external source)
         self.node_pol = {}
@@ -309,6 +310,9 @@ class Primaite(Env):
         for link_key, link_value in self.links.items():
             link_value.clear_traffic()
 
+        for link in self.links_reference.values():
+            link.clear_traffic()
+
         # Create a Transaction (metric) object for this step
         transaction = Transaction(
             datetime.now(), self.agent_identifier, self.episode_count, self.step_count
@@ -346,7 +350,7 @@ class Primaite(Env):
             self.network_reference,
             self.nodes_reference,
             self.links_reference,
-            self.green_iers,
+            self.green_iers_reference,
             self.acl,
             self.step_count,
         )  # Network PoL
@@ -373,6 +377,7 @@ class Primaite(Env):
             self.nodes_post_red,
             self.nodes_reference,
             self.green_iers,
+            self.green_iers_reference,
             self.red_iers,
             self.step_count,
             self.training_config,
@@ -864,6 +869,17 @@ class Primaite(Env):
             ier_destination,
             ier_mission_criticality,
         )
+        self.green_iers_reference[ier_id] = IER(
+            ier_id,
+            ier_start_step,
+            ier_end_step,
+            ier_load,
+            ier_protocol,
+            ier_port,
+            ier_source,
+            ier_destination,
+            ier_mission_criticality,
+        )
 
     def create_red_ier(self, item):
         """
diff --git a/src/primaite/environment/reward.py b/src/primaite/environment/reward.py
index a620f9b3..aa9e4503 100644
--- a/src/primaite/environment/reward.py
+++ b/src/primaite/environment/reward.py
@@ -2,17 +2,21 @@
 """Implements reward function."""
 from typing import Dict
 
+from primaite import getLogger
 from primaite.common.enums import FileSystemState, HardwareState, SoftwareState
 from primaite.common.service import Service
 from primaite.nodes.active_node import ActiveNode
 from primaite.nodes.service_node import ServiceNode
 
+_LOGGER = getLogger(__name__)
+
 
 def calculate_reward_function(
     initial_nodes,
     final_nodes,
     reference_nodes,
     green_iers,
+    green_iers_reference,
     red_iers,
     step_count,
     config_values,
@@ -68,14 +72,36 @@ def calculate_reward_function(
                 reward_value += config_values.red_ier_running
 
     # Go through each green IER - penalise if it's not running (weighted)
+    # but only if it's supposed to be running (it's running in reference)
     for ier_key, ier_value in green_iers.items():
+        reference_ier = green_iers_reference[ier_key]
         start_step = ier_value.get_start_step()
         stop_step = ier_value.get_end_step()
         if step_count >= start_step and step_count <= stop_step:
-            if not ier_value.get_is_running():
-                reward_value += (
-                    config_values.green_ier_blocked
-                    * ier_value.get_mission_criticality()
+            reference_blocked = reference_ier.get_is_running()
+            live_blocked = ier_value.get_is_running()
+            ier_reward = (
+                config_values.green_ier_blocked * ier_value.get_mission_criticality()
+            )
+
+            if live_blocked and not reference_blocked:
+                _LOGGER.debug(
+                    f"Applying reward of {ier_reward} because IER {ier_key} is blocked"
+                )
+                reward_value += ier_reward
+            elif live_blocked and reference_blocked:
+                _LOGGER.debug(
+                    (
+                        f"IER {ier_key} is blocked in the reference and live environments. "
+                        f"Penalty of {ier_reward} was NOT applied."
+                    )
+                )
+            elif not live_blocked and reference_blocked:
+                _LOGGER.debug(
+                    (
+                        f"IER {ier_key} is blocked in the reference env but not in the live one. "
+                        f"Penalty of {ier_reward} was NOT applied."
+                    )
                 )
 
     return reward_value