diff --git a/HLT/Trigger/TrigControl/TrigKernel/CMakeLists.txt b/HLT/Trigger/TrigControl/TrigKernel/CMakeLists.txt
index 81e2589d617c5242ac1565c7c27dd6456c7208c3..3244ba5cbb7ed36c9984cab958282c919da5d04b 100644
--- a/HLT/Trigger/TrigControl/TrigKernel/CMakeLists.txt
+++ b/HLT/Trigger/TrigControl/TrigKernel/CMakeLists.txt
@@ -13,4 +13,4 @@ atlas_add_library( TrigKernel
                    INTERFACE
                    PUBLIC_HEADERS TrigKernel
                    INCLUDE_DIRS ${Boost_INCLUDE_DIRS}
-                   LINK_LIBRARIES GaudiKernel )
+                   LINK_LIBRARIES GaudiKernel CxxUtils )
diff --git a/HLT/Trigger/TrigControl/TrigKernel/TrigKernel/ITrigEventLoopMgr.h b/HLT/Trigger/TrigControl/TrigKernel/TrigKernel/ITrigEventLoopMgr.h
index 7158fce919fd21c310b35938955bf19743a6b070..6a98c51ae21ddbff28d83e359c5694abcf3437a0 100644
--- a/HLT/Trigger/TrigControl/TrigKernel/TrigKernel/ITrigEventLoopMgr.h
+++ b/HLT/Trigger/TrigControl/TrigKernel/TrigKernel/ITrigEventLoopMgr.h
@@ -1,11 +1,12 @@
 /*
-  Copyright (C) 2002-2018 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef TRIGKERNEL_ITRIGEVENTLOOPMGR_H
 #define TRIGKERNEL_ITRIGEVENTLOOPMGR_H
 
 #include "GaudiKernel/IInterface.h"
+#include "CxxUtils/checker_macros.h"
 #include <boost/property_tree/ptree.hpp>
 
 /**@class ITrigEventLoopMgr
@@ -23,7 +24,7 @@ public:
   /**
    * prepareForRun method invoked by framework
    */
-  virtual StatusCode prepareForRun(const boost::property_tree::ptree &) = 0;
+  virtual StatusCode prepareForRun  ATLAS_NOT_THREAD_SAFE (const boost::property_tree::ptree &) = 0;
 
   /**
    * update parameters if necessary after forking workers and issue incident