diff --git a/DDG4/include/DDG4/Geant4Action.h b/DDG4/include/DDG4/Geant4Action.h
index 7e8f74f49..4bdecdd1c 100644
--- a/DDG4/include/DDG4/Geant4Action.h
+++ b/DDG4/include/DDG4/Geant4Action.h
@@ -15,10 +15,10 @@
 #define DDG4_GEANT4ACTION_H
 
 // Framework include files
-#include "DD4hep/Printout.h"
-#include "DD4hep/ComponentProperties.h"
-#include "DDG4/Geant4Context.h"
-#include "DDG4/Geant4Callback.h"
+#include <DD4hep/Printout.h>
+#include <DD4hep/ComponentProperties.h>
+#include <DDG4/Geant4Context.h>
+#include <DDG4/Geant4Callback.h>
 
 // Geant4 forward declarations
 class G4Run;
@@ -113,20 +113,20 @@ namespace dd4hep {
     class Geant4Action {
     protected:
       /// Reference to the Geant4 context
-      Geant4Context*     m_context  {nullptr};
+      Geant4Context*     m_context      { nullptr };
       /// Control directory of this action
-      Geant4UIMessenger* m_control  {nullptr};
+      Geant4UIMessenger* m_control      { nullptr };
 
       /// Default property: Output level
-      int                m_outputLevel  {3};
+      int                m_outputLevel  { 3 };
       /// Default property: Flag to create control instance
-      bool               m_needsControl {false};
+      bool               m_needsControl { false };
       /// Action name
-      std::string        m_name;
+      std::string        m_name         {   };
       /// Property pool
-      PropertyManager    m_properties;
+      PropertyManager    m_properties   {   };
       /// Reference count. Initial value: 1
-      long               m_refCount     {1};
+      long               m_refCount     { 1 };
 
     public:
       /// Functor to update the context of a Geant4Action object
@@ -137,8 +137,8 @@ namespace dd4hep {
        */
       class ContextSwap   {
         /// reference to the context;
-        Geant4Context* context {nullptr};
-        Geant4Action*  action  {nullptr};
+        Geant4Context* context { nullptr };
+        Geant4Action*  action  { nullptr };
       public:
         /// Constructor
         ContextSwap(Geant4Action* a,Geant4Context* c) : action(a)  {
diff --git a/DDG4/include/DDG4/Geant4ActionContainer.h b/DDG4/include/DDG4/Geant4ActionContainer.h
index 8a694dd65..90178fdc3 100644
--- a/DDG4/include/DDG4/Geant4ActionContainer.h
+++ b/DDG4/include/DDG4/Geant4ActionContainer.h
@@ -14,9 +14,9 @@
 #define DDG4_GEANT4ACTIONCONTAINER_H
 
 // Framework include files
-#include "DD4hep/Printout.h"
-#include "DDG4/Geant4Primitives.h"
-#include "DDG4/Geant4Action.h"
+#include <DD4hep/Printout.h>
+#include <DDG4/Geant4Action.h>
+#include <DDG4/Geant4Primitives.h>
 
 // C/C++ include files
 #include <map>
@@ -61,29 +61,29 @@ namespace dd4hep {
     protected:
 
       /// Geant4 worker context (thread specific)
-      Geant4Context*                      m_context;
+      Geant4Context*                      m_context             { nullptr };
 
       /// Reference to the Geant4 primary generator action
-      Geant4GeneratorActionSequence*      m_generatorAction;
+      Geant4GeneratorActionSequence*      m_generatorAction     { nullptr };
       /// Reference to the Geant4 run action
-      Geant4RunActionSequence*            m_runAction;
+      Geant4RunActionSequence*            m_runAction           { nullptr };
       /// Reference to the Geant4 event action
-      Geant4EventActionSequence*          m_eventAction;
+      Geant4EventActionSequence*          m_eventAction         { nullptr };
       /// Reference to the Geant4 track action
-      Geant4TrackingActionSequence*       m_trackingAction;
+      Geant4TrackingActionSequence*       m_trackingAction      { nullptr };
       /// Reference to the Geant4 step action
-      Geant4SteppingActionSequence*       m_steppingAction;
+      Geant4SteppingActionSequence*       m_steppingAction      { nullptr };
       /// Reference to the Geant4 stacking action
-      Geant4StackingActionSequence*       m_stackingAction;
+      Geant4StackingActionSequence*       m_stackingAction      { nullptr };
       /// Reference to the Geant4 detector construction sequence
-      Geant4DetectorConstructionSequence* m_constructionAction;
+      Geant4DetectorConstructionSequence* m_constructionAction  { nullptr };
 
       /// Reference to the Geant4 sensitive action sequences
-      Geant4SensDetSequences*             m_sensDetActions;
+      Geant4SensDetSequences*             m_sensDetActions      { nullptr };
       /// Reference to the Geant4 physics list
-      Geant4PhysicsListActionSequence*    m_physicsList;
+      Geant4PhysicsListActionSequence*    m_physicsList         { nullptr };
       /// Reference to the user initialization object
-      Geant4UserInitializationSequence*   m_userInit;
+      Geant4UserInitializationSequence*   m_userInit            { nullptr };
 
       /// Helper to register an action sequence
       template <typename C> bool registerSequence(C*& seq, const std::string& name);
diff --git a/DDG4/include/DDG4/Geant4ActionPhase.h b/DDG4/include/DDG4/Geant4ActionPhase.h
index 548df73f8..9a8f0275b 100644
--- a/DDG4/include/DDG4/Geant4ActionPhase.h
+++ b/DDG4/include/DDG4/Geant4ActionPhase.h
@@ -14,8 +14,8 @@
 #define DDG4_GEANT4ACTIONPHASE_H
 
 // Framework include files
-#include "DD4hep/Exceptions.h"
-#include "DDG4/Geant4Action.h"
+#include <DD4hep/Exceptions.h>
+#include <DDG4/Geant4Action.h>
 
 // C/C++ include files
 #include <vector>
@@ -70,9 +70,9 @@ namespace dd4hep {
       typedef std::vector<std::pair<Geant4Action*, Callback> > Members;
     protected:
       /// Phase members (actions) being called for a particular phase
-      Members m_members;
+      Members m_members  { };
       /// Type information of the argument type of the callback
-      const std::type_info* m_argTypes[3];
+      const std::type_info* m_argTypes[3] = { nullptr, nullptr, nullptr };
 
     public:
       /// Standard constructor
diff --git a/DDG4/include/DDG4/Geant4AssemblyVolume.h b/DDG4/include/DDG4/Geant4AssemblyVolume.h
index 40141f71c..3865e8a96 100644
--- a/DDG4/include/DDG4/Geant4AssemblyVolume.h
+++ b/DDG4/include/DDG4/Geant4AssemblyVolume.h
@@ -43,9 +43,9 @@ namespace dd4hep {
     public:
 
       typedef std::vector<const TGeoNode*> Chain;
-      std::vector<const TGeoNode*> m_entries;
+      std::vector<const TGeoNode*>       m_entries;
       std::vector<Geant4AssemblyVolume*> m_places;
-      G4AssemblyVolume*            m_assembly;
+      G4AssemblyVolume*                  m_assembly { nullptr };
 
     public:
       /// Default constructor with initialization
diff --git a/DDG4/include/DDG4/Geant4Context.h b/DDG4/include/DDG4/Geant4Context.h
index 3abf31f4f..b801641b0 100644
--- a/DDG4/include/DDG4/Geant4Context.h
+++ b/DDG4/include/DDG4/Geant4Context.h
@@ -68,7 +68,7 @@ namespace dd4hep {
      */
     class  Geant4Run : public ObjectExtensions  {
       /// Reference to the original Geant4 run object
-      const G4Run* m_run;
+      const G4Run* m_run { nullptr };
     protected:
 
     public:
@@ -120,9 +120,9 @@ namespace dd4hep {
      */
     class  Geant4Event : public ObjectExtensions  {
       /// Reference to the original Geant4 event object
-      const G4Event* m_event;
+      const G4Event* m_event  { nullptr };
       /// Reference to the main random number generator
-      Geant4Random* m_random;
+      Geant4Random* m_random  { nullptr };
 
     public:
       /// Intializing constructor
diff --git a/DDG4/include/DDG4/Geant4Converter.h b/DDG4/include/DDG4/Geant4Converter.h
index 2abf2721a..c27b698d3 100644
--- a/DDG4/include/DDG4/Geant4Converter.h
+++ b/DDG4/include/DDG4/Geant4Converter.h
@@ -56,9 +56,9 @@ namespace dd4hep {
       bool printSensitives  = false;
 
       /// Property: Check geometrical overlaps for volume placements and G4 imprints 
-      bool       checkOverlaps;
+      bool       checkOverlaps = true;
       /// Property: Output level for debug printing
-      PrintLevel outputLevel;
+      PrintLevel outputLevel = INFO;
 
       /// Initializing Constructor
       Geant4Converter(const Detector& description);
diff --git a/DDG4/include/DDG4/Geant4Data.h b/DDG4/include/DDG4/Geant4Data.h
index 38757cf12..99e54309d 100644
--- a/DDG4/include/DDG4/Geant4Data.h
+++ b/DDG4/include/DDG4/Geant4Data.h
@@ -50,9 +50,9 @@ namespace dd4hep {
     class SimpleRun {
     public:
       /// Run identifiers
-      int runID;
+      int runID     { -1 };
       /// Number of events in this run
-      int numEvents;
+      int numEvents {  0 };
       /// Default constructor
       SimpleRun();
       /// Default destructor
@@ -71,11 +71,11 @@ namespace dd4hep {
     public:
       typedef std::vector<long> Seeds;
       /// Run identifiers
-      int    runID;
+      int    runID   { -1 };
       /// Event identifier
-      int    eventID;
+      int    eventID { -1 };
       /// Random number generator seeds
-      Seeds  seeds;
+      Seeds  seeds { };
       /// Default constructor
       SimpleEvent();
       /// Default destructor
@@ -269,9 +269,9 @@ namespace dd4hep {
         /// Hit direction
         Direction     momentum;
         /// Length of the track segment contributing to this hit
-        double        length;
+        double        length  { 0e0 };
         /// Energy deposit in the tracker hit
-        double        energyDeposit;
+        double        energyDeposit { 0e0 };
         /// Monte Carlo / Geant4 information
         Contribution  truth;
       public:
@@ -325,11 +325,11 @@ namespace dd4hep {
         typedef Geant4HitData base_t;
 
         /// Hit position
-        Position      position;
+        Position      position      {     };
         /// Hit contributions by individual particles
-        Contributions truth;
+        Contributions truth         {     };
         /// Total energy deposit
-        double        energyDeposit;
+        double        energyDeposit { 0e0 };
       public:
         /// Default constructor (for ROOT)
         Hit();
diff --git a/DDG4/include/DDG4/Geant4DetectorConstruction.h b/DDG4/include/DDG4/Geant4DetectorConstruction.h
index 6fe7826a6..f63b7f937 100644
--- a/DDG4/include/DDG4/Geant4DetectorConstruction.h
+++ b/DDG4/include/DDG4/Geant4DetectorConstruction.h
@@ -15,8 +15,8 @@
 #define DDG4_GEANT4DETECTORCONSTRUCTION_H
 
 // Framework include files
-#include "DD4hep/DetElement.h"
-#include "DDG4/Geant4Action.h"
+#include <DD4hep/DetElement.h>
+#include <DDG4/Geant4Action.h>
 
 // Forward declarations
 class G4VUserDetectorConstruction;
@@ -67,11 +67,11 @@ namespace dd4hep {
       Detector&     description;
 #endif
       /// Reference to the world after construction
-      G4VPhysicalVolume*  world;
+      G4VPhysicalVolume*  world  { nullptr };
       /// The cached geometry information
-      Geant4GeometryInfo* geometry;
+      Geant4GeometryInfo* geometry  { nullptr };
       /// G4 User detector initializer
-      G4VUserDetectorConstruction* detector;
+      G4VUserDetectorConstruction* detector  { nullptr };
       /// Initializing Constructor
       Geant4DetectorConstructionContext(Detector& l,G4VUserDetectorConstruction* d)
         : description(l), world(0), geometry(0), detector(d)  { }
diff --git a/DDG4/include/DDG4/Geant4EventAction.h b/DDG4/include/DDG4/Geant4EventAction.h
index 248ed9036..b31b68e55 100644
--- a/DDG4/include/DDG4/Geant4EventAction.h
+++ b/DDG4/include/DDG4/Geant4EventAction.h
@@ -15,7 +15,7 @@
 #define DDG4_GEANT4EVENTACTION_H
 
 // Framework include files
-#include "DDG4/Geant4Action.h"
+#include <DDG4/Geant4Action.h>
 
 // Forward declarations
 class G4Event;
@@ -85,7 +85,7 @@ namespace dd4hep {
     class Geant4SharedEventAction : public Geant4EventAction {
     protected:
       /// Reference to the shared action
-      Geant4EventAction* m_action = 0;
+      Geant4EventAction* m_action { nullptr };
 
     protected:
       /// Define standard assignments and constructors
diff --git a/DDG4/include/DDG4/Geant4FastSimHandler.h b/DDG4/include/DDG4/Geant4FastSimHandler.h
index d140a778c..36529066b 100644
--- a/DDG4/include/DDG4/Geant4FastSimHandler.h
+++ b/DDG4/include/DDG4/Geant4FastSimHandler.h
@@ -42,7 +42,7 @@ namespace dd4hep {
      */
     class Geant4FastSimHandler  : public Geant4HitHandler  {
     public:
-      const Geant4FastSimSpot* spot;
+      const Geant4FastSimSpot* spot { nullptr };
 
       /// Inhibit default constructor
       Geant4FastSimHandler() = delete;
diff --git a/DDG4/include/DDG4/Geant4FastSimSpot.h b/DDG4/include/DDG4/Geant4FastSimSpot.h
index 5d827f0aa..9d663cecf 100644
--- a/DDG4/include/DDG4/Geant4FastSimSpot.h
+++ b/DDG4/include/DDG4/Geant4FastSimSpot.h
@@ -17,11 +17,11 @@
 #include <DDG4/Defs.h>
 
 // Geant4 include files
-#include "G4Version.hh"
+#include <G4Version.hh>
 
 #if G4VERSION_NUMBER < 1070
 
-#include "G4ThreeVector.hh"
+#include <G4ThreeVector.hh>
 
 class G4FastHit
 {
diff --git a/DDG4/include/DDG4/Geant4Field.h b/DDG4/include/DDG4/Geant4Field.h
index 4c94122a3..1a7ab7288 100644
--- a/DDG4/include/DDG4/Geant4Field.h
+++ b/DDG4/include/DDG4/Geant4Field.h
@@ -15,11 +15,11 @@
 #define DDG4_GEANT4FIELD_H
 
 // Framework include files
-#include "DD4hep/Detector.h"
+#include <DD4hep/Detector.h>
 
 // Geant 4 include files
-#include "G4ElectroMagneticField.hh"
-#include "G4MagneticField.hh"
+#include <G4ElectroMagneticField.hh>
+#include <G4MagneticField.hh>
 
 /// Namespace for the AIDA detector description toolkit
 namespace dd4hep {
diff --git a/DDG4/include/DDG4/Geant4GDMLDetector.h b/DDG4/include/DDG4/Geant4GDMLDetector.h
index 0876fad39..b7bb5405d 100644
--- a/DDG4/include/DDG4/Geant4GDMLDetector.h
+++ b/DDG4/include/DDG4/Geant4GDMLDetector.h
@@ -40,7 +40,7 @@ namespace dd4hep {
       G4VPhysicalVolume* Construct();
     private:
       std::string m_fileName;
-      G4VPhysicalVolume* m_world;
+      G4VPhysicalVolume* m_world { nullptr };
     };
   }
 }
diff --git a/DDG4/include/DDG4/Geant4GeneratorAction.h b/DDG4/include/DDG4/Geant4GeneratorAction.h
index 96b9f230d..a444f5a42 100644
--- a/DDG4/include/DDG4/Geant4GeneratorAction.h
+++ b/DDG4/include/DDG4/Geant4GeneratorAction.h
@@ -14,7 +14,7 @@
 #define DDG4_GEANT4GENERATORACTION_H
 
 // Framework include files
-#include "DDG4/Geant4Action.h"
+#include <DDG4/Geant4Action.h>
 
 // Forward declaration
 class G4Event;
diff --git a/DDG4/include/DDG4/Geant4GeneratorActionInit.h b/DDG4/include/DDG4/Geant4GeneratorActionInit.h
index dfde1081d..74da2e892 100644
--- a/DDG4/include/DDG4/Geant4GeneratorActionInit.h
+++ b/DDG4/include/DDG4/Geant4GeneratorActionInit.h
@@ -15,7 +15,7 @@
 #define DDG4_GEANT4GENERATORACTIONINIT_H
 
 // Framework include files
-#include "DDG4/Geant4GeneratorAction.h"
+#include <DDG4/Geant4GeneratorAction.h>
 
 // Forward declarations
 class G4Event;
@@ -54,11 +54,11 @@ namespace dd4hep {
     class Geant4GeneratorActionInit : public Geant4GeneratorAction    {
     protected:
       /// Current run identifier
-      int m_run;
+      int m_run      {  0 };
       /// Counter for total number of events
-      int m_evtTotal;
+      int m_evtTotal {  0 };
       /// Counter for total number of events in current run
-      int m_evtRun;
+      int m_evtRun   {  0 };
     public:
       /// Standard constructor
       Geant4GeneratorActionInit(Geant4Context* context, const std::string& nam);
diff --git a/DDG4/include/DDG4/Geant4GeneratorWrapper.h b/DDG4/include/DDG4/Geant4GeneratorWrapper.h
index 256ba934c..28bed9bb6 100644
--- a/DDG4/include/DDG4/Geant4GeneratorWrapper.h
+++ b/DDG4/include/DDG4/Geant4GeneratorWrapper.h
@@ -25,7 +25,7 @@
 #define DDG4_GEANT4GENERATORWRAPPER_H
 
 // Framework include files
-#include "DDG4/Geant4GeneratorAction.h"
+#include <DDG4/Geant4GeneratorAction.h>
 
 // Forward declarations
 class G4VPrimaryGenerator;
@@ -49,10 +49,10 @@ namespace dd4hep {
       /// Property: Type name of the implementation instance. name: "Uses"
       std::string m_generatorType;
       /// Property: interaction identifier mask. name: "Mask"
-      int m_mask;
+      int m_mask { 1 };
 
       /// Reference to the implementation instance
-      G4VPrimaryGenerator* m_generator;
+      G4VPrimaryGenerator* m_generator { nullptr };
       
     public:
       /// Standard constructor
diff --git a/DDG4/include/DDG4/Geant4Handle.h b/DDG4/include/DDG4/Geant4Handle.h
index 1fb061774..8431d505c 100644
--- a/DDG4/include/DDG4/Geant4Handle.h
+++ b/DDG4/include/DDG4/Geant4Handle.h
@@ -15,8 +15,8 @@
 #define DDG4_GEANT4HANDLE_H
 
 /// Framework include files
-#include "DD4hep/ComponentProperties.h"
-#include "DD4hep/Detector.h"
+#include <DD4hep/ComponentProperties.h>
+#include <DD4hep/Detector.h>
 
 /// C/C++ include files
 #include <string>
diff --git a/DDG4/include/DDG4/Geant4InputAction.h b/DDG4/include/DDG4/Geant4InputAction.h
index 8da8ad550..5b7202882 100644
--- a/DDG4/include/DDG4/Geant4InputAction.h
+++ b/DDG4/include/DDG4/Geant4InputAction.h
@@ -25,10 +25,10 @@
 #define DDG4_GEANT4INPUTACTION_H
 
 // Framework include files
-#include "DDG4/Geant4Vertex.h"
-#include "DDG4/Geant4Particle.h"
-#include "DDG4/Geant4GeneratorAction.h"
-#include "Parsers/Parsers.h"
+#include <DDG4/Geant4Vertex.h>
+#include <DDG4/Geant4Particle.h>
+#include <DDG4/Geant4GeneratorAction.h>
+#include <Parsers/Parsers.h>
 
 // C/C++ include files
 #include <memory>
@@ -78,11 +78,11 @@ namespace dd4hep  {
       /// File name to be opened and read
       std::string m_name;
       /// Flag if direct event access is supported. To be explicitly set by subclass constructors
-      bool m_directAccess;
+      bool m_directAccess  { false };
       /// Current event number
-      int  m_currEvent;
+      int  m_currEvent     { 0 };
       /// The input action context
-      Geant4InputAction *m_inputAction;
+      Geant4InputAction *m_inputAction   { nullptr };
 
       /// transform the string parameter value into the type of parameter
       /**
diff --git a/DDG4/include/DDG4/Geant4InputHandling.h b/DDG4/include/DDG4/Geant4InputHandling.h
index 2498b541e..d2d5437d3 100644
--- a/DDG4/include/DDG4/Geant4InputHandling.h
+++ b/DDG4/include/DDG4/Geant4InputHandling.h
@@ -15,7 +15,7 @@
 #define DDG4_GEANT4INPUTHANDLING_H
 
 // Framework include files
-#include "DDG4/Geant4Primary.h"
+#include <DDG4/Geant4Primary.h>
 
 // Forward declarations
 class G4Event;
diff --git a/DDG4/include/DDG4/Geant4Kernel.h b/DDG4/include/DDG4/Geant4Kernel.h
index 385174646..5a055c4d0 100644
--- a/DDG4/include/DDG4/Geant4Kernel.h
+++ b/DDG4/include/DDG4/Geant4Kernel.h
@@ -14,7 +14,7 @@
 #define DDG4_GEANT4KERNEL_H
 
 // Framework include files
-#include "DDG4/Geant4ActionContainer.h"
+#include <DDG4/Geant4ActionContainer.h>
 
 // C/C++ include files
 #include <map>
@@ -74,19 +74,19 @@ namespace dd4hep {
       UserFramework      m_userFramework       { };
 
       /// Action phases
-      Phases        m_phases;
+      Phases        m_phases                   { };
       /// Worker threads
-      Workers       m_workers;
+      Workers       m_workers                  { };
       /// Globally registered actions
-      GlobalActions m_globalActions;
+      GlobalActions m_globalActions            { };
       /// Globally registered filters of sensitive detectors
-      GlobalActions m_globalFilters;
+      GlobalActions m_globalFilters            { };
       /// Property: Client output levels
-      ClientOutputLevels m_clientLevels;
+      ClientOutputLevels m_clientLevels        { };
       /// Property: Name of the G4UI command tree
-      std::string m_controlName;
+      std::string   m_controlName              { };
       /// Property: Name of the UI action. Must be member of the global actions
-      std::string m_uiName;
+      std::string   m_uiName                   { };
       /// Property: Name of the G4 run manager factory to be used. Default: Geant4RunManager
       std::string m_runManagerType;
       /// Property: Name of the default factory to create G4VSensitiveDetector instances
@@ -96,7 +96,7 @@ namespace dd4hep {
       /// Property: Number of events to be executed in batch mode
       long        m_numEvent = 10;
       /// Property: Output level
-      int         m_outputLevel;
+      int         m_outputLevel = 0;
 
       /// Master property: Number of execution threads in multi threaded mode.
       int         m_numThreads = 0;
diff --git a/DDG4/include/DDG4/Geant4OutputAction.h b/DDG4/include/DDG4/Geant4OutputAction.h
index 633cd9d9d..e820b5a1c 100644
--- a/DDG4/include/DDG4/Geant4OutputAction.h
+++ b/DDG4/include/DDG4/Geant4OutputAction.h
@@ -14,7 +14,7 @@
 #define DDG4_GEANT4OUTPUTACTION_H
 
 // Framework include files
-#include "DDG4/Geant4EventAction.h"
+#include <DDG4/Geant4EventAction.h>
 
 // Forward declarations
 class G4Run;
@@ -53,11 +53,11 @@ namespace dd4hep {
       };
 
       /// Property: "Output" output destination
-      std::string m_output;
+      std::string        m_output  {  };
       /// Property: "HandleErrorsAsFatal" Handle errors as fatal and rethrow eventual exceptions
-      bool        m_errorFatal;
+      bool               m_errorFatal { true };
       /// Reference to MC truth object
-      Geant4ParticleMap* m_truth;
+      Geant4ParticleMap* m_truth   { nullptr };
     public:
       /// Inhibit default constructor
       Geant4OutputAction() = delete;
diff --git a/DDG4/include/DDG4/Geant4PhysicsList.h b/DDG4/include/DDG4/Geant4PhysicsList.h
index 04c8c912e..32ea6d885 100644
--- a/DDG4/include/DDG4/Geant4PhysicsList.h
+++ b/DDG4/include/DDG4/Geant4PhysicsList.h
@@ -15,7 +15,7 @@
 #define DDG4_GEANT4PHYSICSLIST_H
 
 // Framework include files
-#include "DDG4/Geant4Action.h"
+#include <DDG4/Geant4Action.h>
 
 // C/C++ include files
 #include <map>
@@ -237,9 +237,9 @@ namespace dd4hep {
       virtual void constructDecays(G4VUserPhysicsList* physics);
     public:
       /// Flag if particle transportation is to be added
-      bool m_transportation;
+      bool m_transportation  { false };
       /// Flag if particle decays are to be added
-      bool m_decays;
+      bool m_decays          { false };
       /// Property: Store name of basic predefined Geant4 physics list
       std::string m_extends;
       /// global range cut for secondary productions
diff --git a/DDG4/src/Geant4Action.cpp b/DDG4/src/Geant4Action.cpp
index c8dbd2327..f0f053ad2 100644
--- a/DDG4/src/Geant4Action.cpp
+++ b/DDG4/src/Geant4Action.cpp
@@ -52,8 +52,7 @@ void Geant4Action::ContextUpdate::operator()(Geant4Action* action) const  {
 #endif
 /// Standard constructor
 Geant4Action::Geant4Action(Geant4Context* ctxt, const std::string& nam)
-  : m_context(ctxt), m_control(0), m_outputLevel(INFO), m_needsControl(false), m_name(nam), 
-    m_refCount(1) 
+  : m_context(ctxt), m_outputLevel(INFO), m_name(nam)
 {
   InstanceCount::increment(this);
   m_outputLevel = ctxt ? ctxt->kernel().getOutputLevel(nam) : (printLevel()-1);
diff --git a/DDG4/src/Geant4ActionContainer.cpp b/DDG4/src/Geant4ActionContainer.cpp
index 7fae8020d..e02eed669 100644
--- a/DDG4/src/Geant4ActionContainer.cpp
+++ b/DDG4/src/Geant4ActionContainer.cpp
@@ -35,11 +35,7 @@
 using namespace dd4hep::sim;
 
 /// Standard constructor
-Geant4ActionContainer::Geant4ActionContainer(Geant4Context* ctxt)
-  : m_context(ctxt), 
-    m_generatorAction(0), m_runAction(0), m_eventAction(0), m_trackingAction(0),
-    m_steppingAction(0), m_stackingAction(0), m_constructionAction(0),
-    m_sensDetActions(0), m_physicsList(0), m_userInit(0)
+Geant4ActionContainer::Geant4ActionContainer(Geant4Context* ctxt) : m_context(ctxt)
 {
   m_sensDetActions = new Geant4SensDetSequences();
   InstanceCount::increment(this);
diff --git a/DDG4/src/Geant4AssemblyVolume.cpp b/DDG4/src/Geant4AssemblyVolume.cpp
index 6517b7e03..342fdb761 100644
--- a/DDG4/src/Geant4AssemblyVolume.cpp
+++ b/DDG4/src/Geant4AssemblyVolume.cpp
@@ -42,8 +42,8 @@ Geant4AssemblyVolume::~Geant4AssemblyVolume()   {
 
 /// Place logical daughter volume into the assembly
 long Geant4AssemblyVolume::placeVolume(const TGeoNode* n,
-				       G4LogicalVolume* pPlacedVolume,
-				       G4Transform3D& transformation)
+                                       G4LogicalVolume* pPlacedVolume,
+                                       G4Transform3D& transformation)
 {
   size_t id = m_assembly->TotalTriplets();
   m_entries.emplace_back(n);
@@ -54,8 +54,8 @@ long Geant4AssemblyVolume::placeVolume(const TGeoNode* n,
 
 /// Place daughter assembly into the assembly
 long Geant4AssemblyVolume::placeAssembly(const TGeoNode* n,
-					 Geant4AssemblyVolume* pPlacedVolume,
-					 G4Transform3D& transformation)
+                                         Geant4AssemblyVolume* pPlacedVolume,
+                                         G4Transform3D& transformation)
 {
   size_t id = m_assembly->TotalTriplets();
   m_entries.emplace_back(n);
diff --git a/DDG4/src/Geant4Converter.cpp b/DDG4/src/Geant4Converter.cpp
index 9e5ff305a..183858365 100644
--- a/DDG4/src/Geant4Converter.cpp
+++ b/DDG4/src/Geant4Converter.cpp
@@ -294,10 +294,9 @@ Geant4Converter::Geant4Converter(const Detector& description_ref)
 
 /// Initializing Constructor
 Geant4Converter::Geant4Converter(const Detector& description_ref, PrintLevel level)
-  : Geant4Mapping(description_ref), checkOverlaps(true) {
+  : Geant4Mapping(description_ref), outputLevel(level)  {
   this->Geant4Mapping::init();
   m_propagateRegions = true;
-  outputLevel = level;
 }
 
 /// Standard destructor
diff --git a/DDG4/src/Geant4Data.cpp b/DDG4/src/Geant4Data.cpp
index e4c7efd06..e9b69aee4 100644
--- a/DDG4/src/Geant4Data.cpp
+++ b/DDG4/src/Geant4Data.cpp
@@ -27,8 +27,7 @@
 using namespace dd4hep::sim;
 
 /// Default constructor
-SimpleRun::SimpleRun()
-  : runID(-1), numEvents(0) {
+SimpleRun::SimpleRun()  {
   InstanceCount::increment(this);
 }
 
@@ -38,8 +37,7 @@ SimpleRun::~SimpleRun() {
 }
 
 /// Default constructor
-SimpleEvent::SimpleEvent()
-  : runID(-1), eventID(-1) {
+SimpleEvent::SimpleEvent()  {
   InstanceCount::increment(this);
 }
 
@@ -103,9 +101,7 @@ Geant4HitData::Contribution Geant4HitData::extractContribution(const Geant4FastS
 }
 
 /// Default constructor
-Geant4Tracker::Hit::Hit()
-: Geant4HitData(), position(), momentum(), length(0.0), energyDeposit(0.0), truth()
-{
+Geant4Tracker::Hit::Hit()  {
   InstanceCount::increment(this);
 }
 
@@ -199,14 +195,12 @@ Geant4Tracker::Hit& Geant4Tracker::Hit::storePoint(const Geant4FastSimSpot* spot
 }
 
 /// Default constructor (for ROOT)
-Geant4Calorimeter::Hit::Hit()
-: Geant4HitData(), position(), truth(), energyDeposit(0) {
+Geant4Calorimeter::Hit::Hit()  {
   InstanceCount::increment(this);
 }
 
 /// Standard constructor
-Geant4Calorimeter::Hit::Hit(const Position& pos)
-: Geant4HitData(), position(pos), truth(), energyDeposit(0) {
+Geant4Calorimeter::Hit::Hit(const Position& pos) : position(pos)  {
   InstanceCount::increment(this);
 }
 
diff --git a/DDG4/src/Geant4GDMLDetector.cpp b/DDG4/src/Geant4GDMLDetector.cpp
index b7634f2cf..3ac3ebbf3 100644
--- a/DDG4/src/Geant4GDMLDetector.cpp
+++ b/DDG4/src/Geant4GDMLDetector.cpp
@@ -24,7 +24,7 @@
 #endif
 
 dd4hep::sim::Geant4GDMLDetector::Geant4GDMLDetector(const std::string& gdmlFile)
-  : m_fileName(gdmlFile), m_world(0) {
+  : m_fileName(gdmlFile) {
 }
 
 G4VPhysicalVolume* dd4hep::sim::Geant4GDMLDetector::Construct() {
diff --git a/DDG4/src/Geant4GeneratorActionInit.cpp b/DDG4/src/Geant4GeneratorActionInit.cpp
index 108e827d4..de616060c 100644
--- a/DDG4/src/Geant4GeneratorActionInit.cpp
+++ b/DDG4/src/Geant4GeneratorActionInit.cpp
@@ -12,20 +12,20 @@
 //==========================================================================
 
 // Framework include files
-#include "DD4hep/Printout.h"
-#include "DD4hep/InstanceCount.h"
-#include "DDG4/Geant4Kernel.h"
-#include "DDG4/Geant4RunAction.h"
-#include "DDG4/Geant4GeneratorActionInit.h"
-#include "DDG4/Geant4InputHandling.h"
+#include <DD4hep/Printout.h>
+#include <DD4hep/InstanceCount.h>
+#include <DDG4/Geant4Kernel.h>
+#include <DDG4/Geant4RunAction.h>
+#include <DDG4/Geant4GeneratorActionInit.h>
+#include <DDG4/Geant4InputHandling.h>
 
-#include "G4Run.hh"
+#include <G4Run.hh>
 
 using namespace dd4hep::sim;
 
 /// Standard constructor
 Geant4GeneratorActionInit::Geant4GeneratorActionInit(Geant4Context* ctxt, const std::string& nam)
-  : Geant4GeneratorAction(ctxt,nam), m_run(0), m_evtTotal(0), m_evtRun(0)
+  : Geant4GeneratorAction(ctxt,nam)
 {
   InstanceCount::increment(this);
   context()->kernel().runAction().callAtEnd(this,&Geant4GeneratorActionInit::end);
diff --git a/DDG4/src/Geant4GeneratorWrapper.cpp b/DDG4/src/Geant4GeneratorWrapper.cpp
index a7ab068e0..1e6938264 100644
--- a/DDG4/src/Geant4GeneratorWrapper.cpp
+++ b/DDG4/src/Geant4GeneratorWrapper.cpp
@@ -35,7 +35,7 @@ using namespace dd4hep::sim;
 
 /// Standard constructor
 Geant4GeneratorWrapper::Geant4GeneratorWrapper(Geant4Context* ctxt, const std::string& nam)
-  : Geant4GeneratorAction(ctxt,nam), m_generator(0)
+  : Geant4GeneratorAction(ctxt,nam)
 {
   declareProperty("Uses", m_generatorType);
   declareProperty("Mask", m_mask = 1);
diff --git a/DDG4/src/Geant4InputAction.cpp b/DDG4/src/Geant4InputAction.cpp
index 07ed4e0a9..785f4267b 100644
--- a/DDG4/src/Geant4InputAction.cpp
+++ b/DDG4/src/Geant4InputAction.cpp
@@ -29,8 +29,7 @@ using PropertyMask = dd4hep::detail::ReferenceBitMask<int>;
 
 
 /// Initializing constructor
-Geant4EventReader::Geant4EventReader(const std::string& nam)
-  : m_name(nam), m_directAccess(false), m_currEvent(0), m_inputAction(0)
+Geant4EventReader::Geant4EventReader(const std::string& nam) : m_name(nam)
 {
 }
 
diff --git a/DDG4/src/Geant4Kernel.cpp b/DDG4/src/Geant4Kernel.cpp
index f8c5596f1..00b871b92 100644
--- a/DDG4/src/Geant4Kernel.cpp
+++ b/DDG4/src/Geant4Kernel.cpp
@@ -85,12 +85,11 @@ Geant4ActionPhase& Geant4Kernel::PhaseSelector::operator[](const std::string& na
 
 /// Standard constructor
 Geant4Kernel::Geant4Kernel(Detector& description_ref)
-  : Geant4ActionContainer(), m_runManager(0), m_control(0), m_trackMgr(0), m_detDesc(&description_ref), 
-    m_numThreads(0), m_id(Geant4Kernel::thread_self()), m_master(this), m_shared(0),
-    m_threadContext(0), phase(this)
+  : Geant4ActionContainer(), m_detDesc(&description_ref), 
+    m_id(Geant4Kernel::thread_self()), m_master(this), phase(this)
 {
   m_ident = -1;
-  declareProperty("UI", m_uiName);
+  declareProperty("UI",                   m_uiName);
   declareProperty("OutputLevel",          m_outputLevel = DEBUG);
   declareProperty("NumEvents",            m_numEvent = 10);
   declareProperty("OutputLevels",         m_clientLevels);
@@ -109,11 +108,10 @@ Geant4Kernel::Geant4Kernel(Detector& description_ref)
 
 /// Standard constructor
 Geant4Kernel::Geant4Kernel(Geant4Kernel* krnl, unsigned long ident)
-  : Geant4ActionContainer(), m_runManager(0), m_control(0), m_trackMgr(0), m_detDesc(0),
-    m_numThreads(1), m_id(ident), m_master(krnl), m_shared(0),
-    m_threadContext(0), phase(this)
+  : Geant4ActionContainer(), m_id(ident), m_master(krnl), phase(this)
 {
   char text[64];
+  m_numThreads     = 1; // Slave instance for one single thread
   m_detDesc        = m_master->m_detDesc;
   m_world          = m_master->m_world;
   m_ident          = m_master->m_workers.size();
diff --git a/DDG4/src/Geant4OutputAction.cpp b/DDG4/src/Geant4OutputAction.cpp
index 12c433a3f..ffcbc01db 100644
--- a/DDG4/src/Geant4OutputAction.cpp
+++ b/DDG4/src/Geant4OutputAction.cpp
@@ -26,7 +26,7 @@ using namespace dd4hep::sim;
 
 /// Standard constructor
 Geant4OutputAction::Geant4OutputAction(Geant4Context* ctxt, const std::string& nam)
-  : Geant4EventAction(ctxt, nam), m_truth(0)
+  : Geant4EventAction(ctxt, nam)
 {
   InstanceCount::increment(this);
   declareProperty("Output", m_output);
diff --git a/DDG4/src/Geant4PhysicsList.cpp b/DDG4/src/Geant4PhysicsList.cpp
index cbe2c48a5..eade54531 100644
--- a/DDG4/src/Geant4PhysicsList.cpp
+++ b/DDG4/src/Geant4PhysicsList.cpp
@@ -313,7 +313,8 @@ void Geant4PhysicsList::enable(G4VUserPhysicsList* /* physics */)  {
 
 /// Standard constructor
 Geant4PhysicsListActionSequence::Geant4PhysicsListActionSequence(Geant4Context* ctxt, const std::string& nam)
-  : Geant4Action(ctxt, nam), m_transportation(false), m_decays(false), m_rangecut(0.7*CLHEP::mm)  {
+  : Geant4Action(ctxt, nam), m_rangecut(0.7*CLHEP::mm)
+{
   declareProperty("transportation", m_transportation);
   declareProperty("extends",  m_extends);
   declareProperty("decays",   m_decays);