diff --git a/Trigger/TrigT1/TrigT1CaloCalibTools/CMakeLists.txt b/Trigger/TrigT1/TrigT1CaloCalibTools/CMakeLists.txt
index dea05e30876b4d07b4727f0cf3df81f56a26543e..5c9ff5adc62e1bc85886fef65665c9acba755939 100644
--- a/Trigger/TrigT1/TrigT1CaloCalibTools/CMakeLists.txt
+++ b/Trigger/TrigT1/TrigT1CaloCalibTools/CMakeLists.txt
@@ -12,7 +12,7 @@ atlas_add_library( TrigT1CaloCalibToolsLib
                    src/*.cxx
                    PUBLIC_HEADERS TrigT1CaloCalibTools
                    INCLUDE_DIRS ${ROOT_INCLUDE_DIRS} ${CORAL_INCLUDE_DIRS}
-                   LINK_LIBRARIES ${CORAL_LIBRARIES} ${ROOT_LIBRARIES} AsgTools AthenaBaseComps AthenaKernel AthenaPoolUtilities CaloDetDescrLib CaloEvent CaloIdentifier CaloTriggerToolLib DerivationFrameworkInterfaces GaudiKernel Identifier LArCablingLib LArElecCalib LArIdentifier LArRawEvent LArRecConditions StoreGateLib TileConditionsLib TileEvent TrigT1CaloCalibConditions TrigT1CaloCalibToolInterfaces TrigT1CaloCondSvcLib TrigT1CaloEventLib TrigT1CaloMonitoringToolsLib TrigT1CaloToolInterfaces TrigT1CaloUtilsLib TrigT1Interfaces xAODTrigL1Calo
+                   LINK_LIBRARIES ${CORAL_LIBRARIES} ${ROOT_LIBRARIES} AsgTools AthenaBaseComps AthenaKernel AthenaPoolUtilities CaloDetDescrLib CaloEvent CaloIdentifier CaloTriggerToolLib CxxUtils DerivationFrameworkInterfaces GaudiKernel Identifier LArCablingLib LArElecCalib LArIdentifier LArRawEvent LArRecConditions StoreGateLib TileConditionsLib TileEvent TrigT1CaloCalibConditions TrigT1CaloCalibToolInterfaces TrigT1CaloCondSvcLib TrigT1CaloEventLib TrigT1CaloMonitoringToolsLib TrigT1CaloToolInterfaces TrigT1CaloUtilsLib TrigT1Interfaces xAODTrigL1Calo
                    PRIVATE_LINK_LIBRARIES AthenaMonitoringLib EventInfo LWHists )
 
 atlas_add_component( TrigT1CaloCalibTools
diff --git a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloCells2TriggerTowers.h b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloCells2TriggerTowers.h
index 12b5b5e7575de2ca20da37740723c914cd8e613d..30793d03584dabe8071463b66ef15643b46bf5b3 100644
--- a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloCells2TriggerTowers.h
+++ b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloCells2TriggerTowers.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2019 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef _TRIGGER_TRIGT1_TRIGT1CALOCALIBTOOLS_L1CALOCELLS2TRIGGERTOWERS_H_
@@ -8,6 +8,7 @@
 // Athena Includes
 #include "AsgTools/AsgTool.h"
 #include "GaudiKernel/ToolHandle.h"
+#include "CxxUtils/checker_macros.h"
 #include "StoreGate/StoreGateSvc.h"
 
 // Calo includes
@@ -47,7 +48,9 @@
   */
 
 namespace LVL1 {
-class L1CaloCells2TriggerTowers final : virtual public IL1CaloCells2TriggerTowers, public asg::AsgTool
+
+class ATLAS_NOT_THREAD_SAFE   // use of LArCablingBase
+L1CaloCells2TriggerTowers final : virtual public IL1CaloCells2TriggerTowers, public asg::AsgTool
 {
   /// Create a proper constructor for Athena
   ASG_TOOL_CLASS( L1CaloCells2TriggerTowers , LVL1::IL1CaloCells2TriggerTowers )
diff --git a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloLArTowerEnergy.h b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloLArTowerEnergy.h
index 0324a1222bb79718d792a545102b6e7326a0164f..e27c105778b1fa2b27a24a63ae518f7c64962b79 100644
--- a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloLArTowerEnergy.h
+++ b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloLArTowerEnergy.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2019 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef _TRIGGER_TRIGT1_TRIGT1CALOCALIBTOOLS_L1CALOLARTOWERENERGY_H_
@@ -8,6 +8,7 @@
 // Athena includes
 #include "AsgTools/AsgTool.h"
 #include "GaudiKernel/ToolHandle.h"
+#include "CxxUtils/checker_macros.h"
 #include "StoreGate/StoreGateSvc.h"
 
 #include "Identifier/Identifier.h"
@@ -40,7 +41,8 @@
 
 namespace LVL1 {
 
-class L1CaloLArTowerEnergy : virtual public IL1CaloLArTowerEnergy, public asg::AsgTool
+class ATLAS_NOT_THREAD_SAFE   // use of LArCablingBase
+L1CaloLArTowerEnergy : virtual public IL1CaloLArTowerEnergy, public asg::AsgTool
 {
   /// Create a proper constructor for Athena
   ASG_TOOL_CLASS( L1CaloLArTowerEnergy , LVL1::IL1CaloLArTowerEnergy )
diff --git a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloPprPhos4ShapeCollection.h b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloPprPhos4ShapeCollection.h
index cb833277f7d5e08b96508f01a9e6b6a63f997e7b..fbf55e5fe6d63d63c4da6f3a4ef8d03f719621f7 100644
--- a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloPprPhos4ShapeCollection.h
+++ b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/L1CaloPprPhos4ShapeCollection.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 // ********************************************************
@@ -66,6 +66,7 @@
 
 #include "TrigT1CaloMonitoringTools/TrigT1CaloLWHistogramTool.h"
 #include "GaudiKernel/ToolHandle.h"
+#include "CxxUtils/checker_macros.h"
 
 class TTree;
 class TFile;
@@ -111,7 +112,7 @@ public:
    StatusCode Fill(const L1CaloCoolChannelId& coolId,const unsigned int timeSlice,const unsigned int rodHeaderStep,const int adc);
    StatusCode Fill(const L1CaloCoolChannelId& coolId,const unsigned int rodHeaderStep,const std::vector<int> adc);
    
-   StatusCode Finalize(void);
+   StatusCode Finalize ATLAS_NOT_REENTRANT(void);
    
    TProfile* GetRawSignalShape(const L1CaloCoolChannelId& coolId){return GetMapIterator(coolId)->second->GetRawSignalShape();};
    unsigned int GetRawMaxPeakBin(const L1CaloCoolChannelId& coolId){return GetMapIterator(coolId)->second->GetRawMaxPeakBin();};
diff --git a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/TriggerTowerThinningAlg.h b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/TriggerTowerThinningAlg.h
index fa709b934a6e37c2fc07b825d7f37fc2d257a2bd..a81603779d53ef6c7ddf67c412a46195bbea5640 100644
--- a/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/TriggerTowerThinningAlg.h
+++ b/Trigger/TrigT1/TrigT1CaloCalibTools/TrigT1CaloCalibTools/TriggerTowerThinningAlg.h
@@ -58,11 +58,11 @@ namespace DerivationFramework {
     double m_minRandom;
 
     // Counters
-    mutable unsigned long m_nEventsProcessed;
-    mutable unsigned long m_nEventsAllTriggerTowersKeptByRandom;
-    mutable unsigned long m_nTriggerTowersProcessed;
-    mutable unsigned long m_nTriggerTowersKept;
-    mutable unsigned long m_nTriggerTowersRejected;
+    mutable std::atomic<unsigned long> m_nEventsProcessed;
+    mutable std::atomic<unsigned long> m_nEventsAllTriggerTowersKeptByRandom;
+    mutable std::atomic<unsigned long> m_nTriggerTowersProcessed;
+    mutable std::atomic<unsigned long> m_nTriggerTowersKept;
+    mutable std::atomic<unsigned long> m_nTriggerTowersRejected;
 
     // Tools and random number generator
     TRandom3* m_random;
diff --git a/Trigger/TrigT1/TrigT1CaloCalibTools/src/L1CaloPprPhos4ShapeCollection.cxx b/Trigger/TrigT1/TrigT1CaloCalibTools/src/L1CaloPprPhos4ShapeCollection.cxx
index a00492c4171f2e5a652a932db9b37c0f7ed6cbf6..0c5f9fdf1c31d4b54fa3891ef72d22d4830b4db3 100644
--- a/Trigger/TrigT1/TrigT1CaloCalibTools/src/L1CaloPprPhos4ShapeCollection.cxx
+++ b/Trigger/TrigT1/TrigT1CaloCalibTools/src/L1CaloPprPhos4ShapeCollection.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "TrigT1CaloCalibTools/L1CaloPprPhos4ShapeCollection.h"
@@ -231,7 +231,7 @@ StatusCode L1CaloPprPhos4ShapeCollection::Fill(const L1CaloCoolChannelId& coolId
    return itr->second->Fill(rodHeaderStep, adc);
 }
 
-StatusCode L1CaloPprPhos4ShapeCollection::Finalize(void) {
+StatusCode L1CaloPprPhos4ShapeCollection::Finalize ATLAS_NOT_REENTRANT(void) {
 
    // want to store the profiles and histograms for each cool id into
    // a TTree, which will be output to a file.