diff --git a/src/engine/gameManager/BuildingManager.java b/src/engine/gameManager/BuildingManager.java
index d2905bcd..fcf7b158 100644
--- a/src/engine/gameManager/BuildingManager.java
+++ b/src/engine/gameManager/BuildingManager.java
@@ -335,7 +335,7 @@ public enum BuildingManager {
 
             if (ForgeManager.vendorWorkOrderLookup.get(hirelingNPC) != null)
                 for (WorkOrder workOrder : ForgeManager.vendorWorkOrderLookup.get(hirelingNPC)) {
-                    workOrder.runCompleted = true;
+                    workOrder.runCompleted.set(true);
                     workOrder.vendor = null;
                     DbManager.WarehouseQueries.DELETE_WORKORDER(workOrder);
                 }
diff --git a/src/engine/gameManager/ForgeManager.java b/src/engine/gameManager/ForgeManager.java
index cd621c01..41618f31 100644
--- a/src/engine/gameManager/ForgeManager.java
+++ b/src/engine/gameManager/ForgeManager.java
@@ -65,7 +65,7 @@ public enum ForgeManager implements Runnable {
                 // Early exit for completed workOrders loaded from disk
                 // or vendors who were re-deeded with items cooking.
 
-                if (workOrder.vendor == null && workOrder.runCompleted)
+                if (workOrder.vendor == null && workOrder.runCompleted.get())
                     continue;
 
                 // This workOrder has completed production.
@@ -82,7 +82,7 @@ public enum ForgeManager implements Runnable {
                         DispatchMessage.dispatchMsgToInterestArea(workOrder.vendor, outMsg, mbEnums.DispatchChannel.SECONDARY, 700, false, false);
                     }
 
-                    workOrder.runCompleted = true;
+                    workOrder.runCompleted.set(true);
 
                     // Update workOrder on disk
 
@@ -150,9 +150,9 @@ public enum ForgeManager implements Runnable {
             workOrder.workOrderID = workOrderCounter.incrementAndGet();
             workOrder.rollingDuration = ForgeManager.calcRollingDuration(workOrder);
             workOrder.completionTime = System.currentTimeMillis() + workOrder.rollingDuration;
-            workOrder.slots_used = calcAvailableSlots(workOrder);
+            workOrder.slots_used.set(calcAvailableSlots(workOrder));
 
-            if (workOrder.slots_used == 0)
+            if (workOrder.slots_used.get() == 0)
                 return 58;
 
             workOrder.total_produced = 0;
@@ -164,7 +164,7 @@ public enum ForgeManager implements Runnable {
 
             // Set total cost for production run
 
-            workOrder.total_to_produce *= workOrder.slots_used;
+            workOrder.total_to_produce *= workOrder.slots_used.get();
 
             workOrder.production_cost = calcProductionCost(workOrder);
             workOrder.production_cost.forEach((key, value) -> workOrder.production_cost_total.put(key, value * workOrder.total_to_produce));
@@ -366,7 +366,7 @@ public enum ForgeManager implements Runnable {
 
         workOrder.completionTime = System.currentTimeMillis() + workOrder.rollingDuration;
 
-        for (int i = 0; i < workOrder.slots_used; ++i) {
+        for (int i = 0; i < workOrder.slots_used.get(); ++i) {
 
             Item forged_item = forgeItem(workOrder);
 
diff --git a/src/engine/loot/WorkOrder.java b/src/engine/loot/WorkOrder.java
index 1d0ead4f..90053de2 100644
--- a/src/engine/loot/WorkOrder.java
+++ b/src/engine/loot/WorkOrder.java
@@ -29,6 +29,8 @@ import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Delayed;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
 
 public class WorkOrder implements Delayed {
 
@@ -41,7 +43,7 @@ public class WorkOrder implements Delayed {
 
     public int workOrderID;
     public NPC vendor;
-    public volatile int slots_used;
+    public AtomicInteger slots_used = new AtomicInteger(0);
     public int total_to_produce;
     public int total_produced;
     public boolean multiple_slot_request;
@@ -53,7 +55,7 @@ public class WorkOrder implements Delayed {
     public int suffixToken;
     public long rollingDuration;
     public long completionTime;
-    public volatile boolean runCompleted = false;
+    public AtomicBoolean runCompleted = new AtomicBoolean(false);
 
     // This collection is serialized to the vendor rolling window in ManageNPCMsg.
 
@@ -70,7 +72,7 @@ public class WorkOrder implements Delayed {
 
         this.workOrderID = jsonWorkOrder.getInt("workOrderID");
         this.vendor = NPC.getNPC(jsonWorkOrder.getInt("vendor"));
-        this.slots_used = jsonWorkOrder.getInt("slots_used");
+        this.slots_used.set(jsonWorkOrder.getInt("slots_used"));
         this.total_to_produce = jsonWorkOrder.getInt("total_to_produce");
         this.total_produced = jsonWorkOrder.getInt("total_produced");
         this.multiple_slot_request = jsonWorkOrder.getBoolean("multiple_slot_request");
@@ -78,10 +80,9 @@ public class WorkOrder implements Delayed {
         this.item_name_override = jsonWorkOrder.getString("item_name_override");
         this.prefixToken = jsonWorkOrder.getInt("prefixToken");
         this.suffixToken = jsonWorkOrder.getInt("suffixToken");
-        this.slots_used = jsonWorkOrder.getInt("slots_used");
         this.rollingDuration = jsonWorkOrder.getLong("rollingDuration");
         this.completionTime = jsonWorkOrder.getLong("completionTime");
-        this.runCompleted = jsonWorkOrder.getBoolean("runCompleted");
+        this.runCompleted.set(jsonWorkOrder.getBoolean("runCompleted"));
 
         JSONObject productionCostMap = jsonWorkOrder.getJSONObject("production_cost");
 
diff --git a/src/engine/net/client/handlers/ItemProductionMsgHandler.java b/src/engine/net/client/handlers/ItemProductionMsgHandler.java
index cdc5ce81..3629105c 100644
--- a/src/engine/net/client/handlers/ItemProductionMsgHandler.java
+++ b/src/engine/net/client/handlers/ItemProductionMsgHandler.java
@@ -150,7 +150,7 @@ public class ItemProductionMsgHandler extends AbstractClientMsgHandler {
             ForgeManager.itemWorkOrderLookup.remove(virtualItem);
             DbManager.removeFromCache(virtualItem);
 
-            workOrder.slots_used = workOrder.slots_used - 1;
+            workOrder.slots_used.set(workOrder.slots_used.get() - 1);
 
             // Update workOrder on disk
 
@@ -421,15 +421,15 @@ public class ItemProductionMsgHandler extends AbstractClientMsgHandler {
             // Update total_to_produce accounting for the slot being
             // removed while workOrder is not completed.
 
-            if (!workOrder.runCompleted)
-                if (workOrder.multiple_slot_request && workOrder.slots_used > 1) {
-                    int itemsPerSlot = workOrder.total_to_produce / workOrder.slots_used;
+            if (!workOrder.runCompleted.get())
+                if (workOrder.multiple_slot_request && workOrder.slots_used.get() > 1) {
+                    int itemsPerSlot = workOrder.total_to_produce / workOrder.slots_used.get();
                     workOrder.total_to_produce = workOrder.total_to_produce - itemsPerSlot;
                 }
 
             // Slot is no longer allocated to this workOrder.
 
-            workOrder.slots_used = workOrder.slots_used - 1;
+            workOrder.slots_used.set(workOrder.slots_used.get() - 1);
 
             // Update workOrder on disk