diff --git a/BauSystem_Main/src/de/steamwar/bausystem/features/simulator/TNTSimulatorListener.java b/BauSystem_Main/src/de/steamwar/bausystem/features/simulator/TNTSimulatorListener.java
index 374d1192..41d6e1ed 100644
--- a/BauSystem_Main/src/de/steamwar/bausystem/features/simulator/TNTSimulatorListener.java
+++ b/BauSystem_Main/src/de/steamwar/bausystem/features/simulator/TNTSimulatorListener.java
@@ -116,6 +116,10 @@ public class TNTSimulatorListener implements Listener {
         if (simulator == null) return;
         Pair<Integer, Map<Integer, List<List<Pair<TNTData, Integer>>>>> toCalculate = simulator.locations(event.getPlayer());
         PreviewRecord previewRecord = Simulator.impl.run(toCalculate);
+        if (previewRecord == null) {
+            event.setCancelled(true);
+            return;
+        }
         previewRecord.add(event.getPlayer());
     }