diff --git a/CMakeLists.txt b/CMakeLists.txt
index 92e4d3b..a92acf1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.0.0 FATAL_ERROR)
 
-project(IRT
+project(IRT2
   VERSION 2.1.0
   LANGUAGES CXX
 )
diff --git a/cmake/IRTConfig.cmake.in b/cmake/IRT2Config.cmake.in
similarity index 85%
rename from cmake/IRTConfig.cmake.in
rename to cmake/IRT2Config.cmake.in
index 102d9ff..f3aa316 100644
--- a/cmake/IRTConfig.cmake.in
+++ b/cmake/IRT2Config.cmake.in
@@ -2,4 +2,4 @@
 include("@PACKAGE_TARGETS_INSTALL_PATH@")
 set_and_check(IRT_INCLUDE_DIR "@PACKAGE_CMAKE_INSTALL_INCLUDEDIR@")
 set_and_check(IRT_LIBRARY_DIR "@PACKAGE_CMAKE_INSTALL_LIBDIR@")
-check_required_components(IRT)
+check_required_components(IRT2)
diff --git a/include/BitMask.h b/include/BitMask.h
index 9f9a89c..b1337c3 100644
--- a/include/BitMask.h
+++ b/include/BitMask.h
@@ -1,8 +1,8 @@
+#pragma once
 
 #include <TObject.h>
 
-#ifndef _BIT_MASK_
-#define _BIT_MASK_
+namespace IRT2 {
 
 class BitMask: public TObject {
  public:
@@ -24,4 +24,4 @@ class BitMask: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/Calibration.h b/include/Calibration.h
index 89b3b13..ca3a80d 100644
--- a/include/Calibration.h
+++ b/include/Calibration.h
@@ -1,18 +1,18 @@
+#pragma once
 
 #include <map>
 
 class TDatabasePDG;
 #include <TRandom.h>
 
-#ifndef _CALIBRATION_
-#define _CALIBRATION_
-
 #include "GeantImport.h"
 
 // 5 degree binning for calibration purposes suffices?;
 #define _THETA_BIN_COUNT_ (180/5)
 #define _THETA_BIN_WIDTH_ (M_PI / _THETA_BIN_COUNT_)
 
+namespace IRT2 {
+
 class Calibration : public virtual GeantImport {
  public:
   Calibration ();
@@ -69,5 +69,4 @@ class Calibration : public virtual GeantImport {
   double m_DefaultSinglePhotonThetaResolution;
 };
 
-
-#endif
+} // namespace IRT2
diff --git a/include/ChargedParticle.h b/include/ChargedParticle.h
index 6731564..40d8f2c 100644
--- a/include/ChargedParticle.h
+++ b/include/ChargedParticle.h
@@ -1,17 +1,17 @@
+#pragma once
 
 #include <vector>
 
 #include <TRef.h>
 
-#ifndef _CHARGED_PARTICLE_
-#define _CHARGED_PARTICLE_
-
 #include "CherenkovRadiator.h"
 #include "RadiatorHistory.h"
 #include "TransientParticle.h"
 #include "CherenkovPID.h"
 #include "DigitizedHit.h"
 
+namespace IRT2 {
+
 class ChargedParticle: public TransientParticle {
  public:
  ChargedParticle(int pdg = 0, bool primary = true): 
@@ -107,4 +107,4 @@ class ChargedParticle: public TransientParticle {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/ChargedParticleStep.h b/include/ChargedParticleStep.h
index 8fc8666..4dead64 100644
--- a/include/ChargedParticleStep.h
+++ b/include/ChargedParticleStep.h
@@ -1,9 +1,9 @@
+#pragma once
 
 #include <TObject.h>
 #include <TVector3.h>
 
-#ifndef _CHARGED_PARTICLE_STEP_
-#define _CHARGED_PARTICLE_STEP_
+namespace IRT2 {
 
 class ChargedParticleStep: public TObject {
  public:
@@ -28,4 +28,4 @@ class ChargedParticleStep: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovDetector.h b/include/CherenkovDetector.h
index b14f03d..382ff41 100644
--- a/include/CherenkovDetector.h
+++ b/include/CherenkovDetector.h
@@ -1,4 +1,3 @@
-
 #pragma once
 
 #include <vector>
@@ -7,14 +6,13 @@
 #include <TRef.h>
 #include <TString.h>
 
-#ifndef _CHERENKOV_DETECTOR_
-#define _CHERENKOV_DETECTOR_
-
 #include "CherenkovPhotonDetector.h"
 class CherenkovMirrorGroup;
 class OpticalBoundary;
 class G4LogicalVolume;
 
+namespace IRT2 {
+
 class CherenkovDetector: public TObject {
  public:
  CherenkovDetector(const char *name = 0): /*m_ContainerVolume(0),*/ m_Name(name ? name : ""), 
@@ -164,4 +162,4 @@ class CherenkovDetector: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovDetectorCollection.h b/include/CherenkovDetectorCollection.h
index 97fc8e2..2692ff0 100644
--- a/include/CherenkovDetectorCollection.h
+++ b/include/CherenkovDetectorCollection.h
@@ -1,9 +1,7 @@
+#pragma once
 
 #include <map>
 
-#ifndef _CHERENKOV_DETECTOR_COLLECTION_
-#define _CHERENKOV_DETECTOR_COLLECTION_
-
 class G4LogicalVolume;
 class G4RadiatorMaterial;
 class G4OpticalSurface;
@@ -18,6 +16,8 @@ class CherenkovPhotonDetector;
 #define _STORE_REFLECTION_POINTS_ (0x00000002)
 #define _STORE_REFRACTION_POINTS_ (0x00000003)
 
+namespace IRT2 {
+
 class CherenkovDetectorCollection: public BitMask {
  public:
   CherenkovDetectorCollection() {};
@@ -163,4 +163,4 @@ class CherenkovDetectorCollection: public BitMask {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovEvent.h b/include/CherenkovEvent.h
index 92b4107..eb01005 100644
--- a/include/CherenkovEvent.h
+++ b/include/CherenkovEvent.h
@@ -1,13 +1,13 @@
+#pragma once
 
 #include <set>
 
-#ifndef _CHERENKOV_EVENT_
-#define _CHERENKOV_EVENT_
-
 #include "ChargedParticle.h"
 
 class OpticalPhoton;
 
+namespace IRT2 {
+
 class CherenkovEvent: public TObject {
  public:
   CherenkovEvent() {};
@@ -39,4 +39,4 @@ class CherenkovEvent: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovMirror.h b/include/CherenkovMirror.h
index 84f5be6..8fe479a 100644
--- a/include/CherenkovMirror.h
+++ b/include/CherenkovMirror.h
@@ -1,6 +1,4 @@
-
-#ifndef _CHERENKOV_MIRROR_
-#define _CHERENKOV_MIRROR_
+#pragma once
 
 #include "G4Object.h"
 #include "FlatSurface.h"
@@ -11,6 +9,8 @@
 
 class CherenkovWaveLengthRange;
 
+namespace IRT2 {
+
 class SurfaceCopy: public G4ObjectCopy {
  public:
  SurfaceCopy(G4VPhysicalVolume *phys = 0): G4ObjectCopy(phys), m_Surface(0) {};
@@ -101,4 +101,4 @@ class ConicalMirror: public CherenkovMirror, public ConicalSurface {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovPID.h b/include/CherenkovPID.h
index 2e85e0d..1d5db29 100644
--- a/include/CherenkovPID.h
+++ b/include/CherenkovPID.h
@@ -1,10 +1,10 @@
+#pragma once
 
 #include <algorithm>
 #include <map>
 #include <vector>
 
-#ifndef _CHERENKOV_PID_
-#define _CHERENKOV_PID_
+namespace IRT2 {
 
 class CherenkovRadiator;
 
@@ -73,4 +73,4 @@ class CherenkovPID {
   std::vector<MassHypothesis*> m_Hypotheses;
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovPhotonDetector.h b/include/CherenkovPhotonDetector.h
index 99ca78e..323b6e3 100644
--- a/include/CherenkovPhotonDetector.h
+++ b/include/CherenkovPhotonDetector.h
@@ -1,9 +1,7 @@
+#pragma once
 
 #include <map>
 
-#ifndef _CHERENKOV_PHOTON_DETECTOR_
-#define _CHERENKOV_PHOTON_DETECTOR_
-
 #include "G4Object.h"
 #include "FlatSurface.h"
 
@@ -11,6 +9,8 @@ class G4DataInterpolation;
 
 #include "IRT.h"
 
+namespace IRT2 {
+
 class CherenkovPhotonDetector: public G4Object {
  public:
  CherenkovPhotonDetector(G4VSolid *solid = 0, G4Material *material = 0):
@@ -96,4 +96,4 @@ class CherenkovPhotonDetector: public G4Object {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovRadiator.h b/include/CherenkovRadiator.h
index 5deb58e..816813a 100644
--- a/include/CherenkovRadiator.h
+++ b/include/CherenkovRadiator.h
@@ -1,3 +1,4 @@
+#pragma once
 
 #include <map>
 #include <vector>
@@ -8,15 +9,14 @@
 #include <TString.h>
 class TH1D;
 
-#ifndef _CHERENKOV_RADIATOR_
-#define _CHERENKOV_RADIATOR_
-
 #include "ParametricSurface.h"
 class G4LogicalVolume;
 class G4RadiatorMaterial;
 
 class G4DataInterpolation;
 
+namespace IRT2 {
+
 struct CherenkovRadiatorCalibration: public TObject {
   CherenkovRadiatorCalibration(): m_Stat(0), 
     m_AverageZvtx(0.0), m_hcalib(0), m_Coffset(0.0), m_Csigma(0.0) {};
@@ -193,4 +193,4 @@ class CherenkovRadiator: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CherenkovWaveLengthRange.h b/include/CherenkovWaveLengthRange.h
index a7fc673..13fe38e 100644
--- a/include/CherenkovWaveLengthRange.h
+++ b/include/CherenkovWaveLengthRange.h
@@ -1,6 +1,6 @@
+#pragma once
 
-#ifndef _CHERENKOV_WAVELENGTH_RANGE_
-#define _CHERENKOV_WAVELENGTH_RANGE_
+namespace IRT2 {
 
 class CherenkovWaveLengthRange {
 public:
@@ -24,4 +24,4 @@ class CherenkovWaveLengthRange {
   double *m_PhotonEnergies;
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/ConicalSurface.h b/include/ConicalSurface.h
index b982807..5684960 100644
--- a/include/ConicalSurface.h
+++ b/include/ConicalSurface.h
@@ -1,8 +1,8 @@
+#pragma once
 
 #include "ParametricSurface.h"
 
-#ifndef _IRT_CONICAL_SURFACE_
-#define _IRT_CONICAL_SURFACE_
+namespace IRT2 {
 
 class ConicalSurface: public ParametricSurface {
  public:
@@ -82,4 +82,4 @@ class ConicalSurface: public ParametricSurface {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/CylindricalSurface.h b/include/CylindricalSurface.h
index e740521..0563543 100644
--- a/include/CylindricalSurface.h
+++ b/include/CylindricalSurface.h
@@ -1,3 +1,4 @@
+#pragma once
 
 //
 // Yes, prefer to keep it separately even that it is a subset of a ConicalSurface;
@@ -5,8 +6,7 @@
 
 #include "ParametricSurface.h"
 
-#ifndef _IRT_CYLINDRICAL_SURFACE_
-#define _IRT_CYLINDRICAL_SURFACE_
+namespace IRT2 {
 
 class CylindricalSurface: public ParametricSurface {
  public:
@@ -78,4 +78,4 @@ class CylindricalSurface: public ParametricSurface {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/Digitization.h b/include/Digitization.h
index 0ab3a0e..a90203c 100644
--- a/include/Digitization.h
+++ b/include/Digitization.h
@@ -1,11 +1,12 @@
+#pragma once
 
 #include <TRandom.h>
 
-#ifndef _DIGITIZATION_
-#define _DIGITIZATION_
-
 #include "DigitizedHit.h"
 #include "GeantImport.h"
+
+namespace IRT2 {
+
 class CherenkovPhotonDetector;
 
 struct BlackoutCell {
@@ -66,4 +67,4 @@ class Digitization : public virtual GeantImport {
   unsigned m_SensorActiveAreaPixellation;
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/DigitizedHit.h b/include/DigitizedHit.h
index 9ccef6d..90a3168 100644
--- a/include/DigitizedHit.h
+++ b/include/DigitizedHit.h
@@ -1,3 +1,4 @@
+#pragma once
 
 #include <set>
 #include <map>
@@ -6,11 +7,11 @@
 #include <TObject.h>
 #include <TVector3.h>
 
-#ifndef _DIGITIZED_HIT_
-#define _DIGITIZED_HIT_
-
 #include "CherenkovPhotonDetector.h"
 #include "SinglePDF.h"
+
+namespace IRT2 {
+
 class ChargedParticle;
 class IRT;
 
@@ -87,4 +88,5 @@ class DigitizedHit {
   //TVector3 m_PhotonVertexPosition;                                //!
   //TVector3 m_PhotonVertexMomentum;                                //!
 };
-#endif
+
+} // namespace IRT2
diff --git a/include/FlatSurface.h b/include/FlatSurface.h
index 4567426..3978bb1 100644
--- a/include/FlatSurface.h
+++ b/include/FlatSurface.h
@@ -1,8 +1,8 @@
+#pragma once
 
 #include "ParametricSurface.h"
 
-#ifndef _IRT_FLAT_SURFACE_
-#define _IRT_FLAT_SURFACE_
+namespace IRT2 {
 
 // In fact a rectangle in space;
 class FlatSurface: public ParametricSurface, public LocalCoordinatesXY {
@@ -58,4 +58,4 @@ class FlatSurface: public ParametricSurface, public LocalCoordinatesXY {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/G4Object.h b/include/G4Object.h
index 474ba98..e5b1139 100644
--- a/include/G4Object.h
+++ b/include/G4Object.h
@@ -1,9 +1,7 @@
+#pragma once
 
 #include <TObject.h>
 
-#ifndef _G4_OBJECT_
-#define _G4_OBJECT_
-
 class G4Material;
 class G4VPhysicalVolume;
 class G4LogicalVolume;
@@ -20,6 +18,8 @@ class G4RotationMatrix;
 class G4ThreeVector;
 #endif
 
+namespace IRT2 {
+
 class G4ObjectCopy: public TObject {
  public:
  G4ObjectCopy(G4VPhysicalVolume *phys = 0): m_PhysicalVolume(phys) {};
@@ -79,4 +79,4 @@ class G4Object: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/GeantImport.h b/include/GeantImport.h
index dc5458f..7a4d969 100644
--- a/include/GeantImport.h
+++ b/include/GeantImport.h
@@ -1,15 +1,16 @@
+#pragma once
 
 #include <TTree.h>
 
-#ifndef _GEANT_IMPORT_
-#define _GEANT_IMPORT_
-
 #include "CherenkovEvent.h"
-class CherenkovDetectorCollection;
-class CherenkovDetector;
 
 #define _MOMENTUM_CUTOFF_DEFAULT_ (0.010)
 
+namespace IRT2 {
+
+class CherenkovDetectorCollection;
+class CherenkovDetector;
+
 class GeantImport {
  public:
   GeantImport(const char *dfname = 0, const char *cfname = 0, const char *dname = 0);
@@ -46,8 +47,8 @@ class GeantImport {
   // Input (GEANT) / output(Reco) event structure;
   CherenkovEvent *m_Event;
 
-  bool m_PurgeSecondaries; 
+  bool m_PurgeSecondaries;
   double m_MomentumCutoff;
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/IRT.h b/include/IRT.h
index 1bb4245..f2df984 100644
--- a/include/IRT.h
+++ b/include/IRT.h
@@ -1,3 +1,4 @@
+#pragma once
 
 #include <vector>
 
@@ -5,9 +6,6 @@
 #include <TObject.h>
 #include <TRef.h>
 
-#ifndef _IRT_FACTORY_
-#define _IRT_FACTORY_
-
 // Don't even care about the units here; [mm] in fact; just make it practically small;
 #define _IRT_PRECISION_DEFAULT_     (1E-7)
 // Well, assume radians in [theta,phi] -> 1urad step should be good enough;
@@ -24,6 +22,8 @@
 #include "ParametricSurface.h"
 #include "IRTSolution.h"
 
+namespace IRT2 {
+
 class IRT: public TObject {
  public:
   IRT(/*unsigned sector = 0*/): /*m_Sector(sector),*/ m_IterationLimit(_IRT_ITERATION_LIMIT_), 
@@ -70,4 +70,4 @@ class IRT: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/IRTSolution.h b/include/IRTSolution.h
index 44af9d8..05969f6 100644
--- a/include/IRTSolution.h
+++ b/include/IRTSolution.h
@@ -1,8 +1,8 @@
+#pragma once
 
 #include <TVector3.h>
 
-#ifndef _IRT_SOLUTION_
-#define _IRT_SOLUTION_
+namespace IRT2 {
 
 class IRTSolution {
   friend class IRT;
@@ -65,4 +65,4 @@ class IRTSolution {
   double m_SigmaDx, m_SigmaDy, m_SigmaDz, m_SigmaDt, m_SigmaDf;
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/OpticalBoundary.h b/include/OpticalBoundary.h
index bad9022..eaa6a1d 100644
--- a/include/OpticalBoundary.h
+++ b/include/OpticalBoundary.h
@@ -1,11 +1,12 @@
+#pragma once
 
 #include <TRef.h>
 #include <TObject.h>
 
-#ifndef _OPTICAL_BOUNDARY_
-#define _OPTICAL_BOUNDARY_
-
 #include "CherenkovRadiator.h"
+
+namespace IRT2 {
+
 class ParametricSurface;
 
 class OpticalBoundary: public TObject {
@@ -42,4 +43,4 @@ class OpticalBoundary: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/OpticalPhoton.h b/include/OpticalPhoton.h
index d87ffe2..f8becae 100644
--- a/include/OpticalPhoton.h
+++ b/include/OpticalPhoton.h
@@ -1,3 +1,4 @@
+#pragma once
 
 #include <set>
 #include <map>
@@ -5,16 +6,16 @@
 
 #include <TVector3.h>
 
-#ifndef _OPTICAL_PHOTON_
-#define _OPTICAL_PHOTON_
-
 #include "TransientParticle.h"
 #include "CherenkovPhotonDetector.h"
-class ReflectionPoint;
-class ChargedParticle;
 #include "RefractionPoint.h"
 #include "SinglePDF.h"
 
+namespace IRT2 {
+
+class ReflectionPoint;
+class ChargedParticle;
+
 class OpticalPhoton: public TransientParticle {
  public:
  OpticalPhoton(): TransientParticle(0), m_VertexAttenuationLength(0.0), 
@@ -111,4 +112,4 @@ class OpticalPhoton: public TransientParticle {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/ParametricSurface.h b/include/ParametricSurface.h
index 6859253..5ca3432 100644
--- a/include/ParametricSurface.h
+++ b/include/ParametricSurface.h
@@ -1,11 +1,11 @@
+#pragma once
 
 #include <math.h>
 
 #include <TObject.h>
 #include <TVector3.h>
 
-#ifndef _IRT_PARAMETRIC_SURFACE_
-#define _IRT_PARAMETRIC_SURFACE_
+namespace IRT2 {
 
 class ParametricSurface: public TObject {
  public:
@@ -87,6 +87,6 @@ class LocalCoordinatesXY: public TObject {
 #ifndef DISABLE_ROOT_IO
   ClassDef(LocalCoordinatesXY, 1);
 #endif
-}; 
+};
 
-#endif
+} // namespace IRT2
diff --git a/include/RadiatorHistory.h b/include/RadiatorHistory.h
index 830995f..4a4fd01 100644
--- a/include/RadiatorHistory.h
+++ b/include/RadiatorHistory.h
@@ -1,15 +1,15 @@
+#pragma once
 
 #include <map>
 #include <vector>
 
 #include <TObject.h>
 
-#ifndef _RADIATOR_HISTORY_
-#define _RADIATOR_HISTORY_
-
 #include "OpticalPhoton.h"
 #include "ChargedParticleStep.h"
 
+namespace IRT2 {
+
 class RadiatorHistory: public TObject {
  public:
  RadiatorHistory(): m_EstimatedPath(0.0)/*, m_AverageTime(0.0)*/ {};
@@ -83,4 +83,4 @@ class RadiatorHistory: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/ReconstructionFactory.h b/include/ReconstructionFactory.h
index f491152..0c3f733 100644
--- a/include/ReconstructionFactory.h
+++ b/include/ReconstructionFactory.h
@@ -1,11 +1,11 @@
+#pragma once
 
 class TParticlePDG;
 
 #include "Calibration.h"
 #include "Digitization.h"
 
-#ifndef _RECONSTRUCTION_FACTORY_
-#define _RECONSTRUCTION_FACTORY_
+namespace IRT2 {
 
 struct ReconstructionFactoryPlots {
   ReconstructionFactoryPlots();
@@ -96,4 +96,4 @@ class ReconstructionFactory : public Digitization, public Calibration {
   void LaunchRingFinder(bool calibration);
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/ReflectionPoint.h b/include/ReflectionPoint.h
index d0a0834..aa53117 100644
--- a/include/ReflectionPoint.h
+++ b/include/ReflectionPoint.h
@@ -1,13 +1,13 @@
+#pragma once
 
 #include <TObject.h>
 #include <TVector3.h>
 #include <TRef.h>
 
-#ifndef _REFLECTION_POINT_
-#define _REFLECTION_POINT_
-
 #include "CherenkovMirror.h"
 
+namespace IRT2 {
+
 class ReflectionPoint: public TObject {
  public:
  ReflectionPoint(): m_Mirror(0)/*, m_VolumeCopy(0)*/ {};
@@ -25,4 +25,4 @@ class ReflectionPoint: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/RefractionPoint.h b/include/RefractionPoint.h
index 66c8cab..7eeee27 100644
--- a/include/RefractionPoint.h
+++ b/include/RefractionPoint.h
@@ -1,13 +1,13 @@
+#pragma once
 
 #include <TObject.h>
 #include <TVector3.h>
 #include <TRef.h>
 
-#ifndef _REFRACTION_POINT_
-#define _REFRACTION_POINT_
-
 #include "CherenkovRadiator.h"
 
+namespace IRT2 {
+
 class RefractionPoint: public TObject {
  public:
   RefractionPoint()/*: m_Mirror(0), m_VolumeCopy(0)*/ { m_Radiators[0] = 0; m_Radiators[1] = 0; };
@@ -30,4 +30,4 @@ class RefractionPoint: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/SinglePDF.h b/include/SinglePDF.h
index 1cada40..74f2232 100644
--- a/include/SinglePDF.h
+++ b/include/SinglePDF.h
@@ -1,11 +1,11 @@
+#pragma once
 
 #include <vector>
 #include <math.h>
 
 #include <TObject.h>
 
-#ifndef _SINGLE_PDF_
-#define _SINGLE_PDF_
+namespace IRT2 {
 
 class SinglePDF: public TObject {
  public:
@@ -166,5 +166,4 @@ class VectorPDF: public TObject {
 #endif
 };
 
-
-#endif
+} // namespace IRT2
diff --git a/include/SphericalSurface.h b/include/SphericalSurface.h
index 9cec9f2..74b9b82 100644
--- a/include/SphericalSurface.h
+++ b/include/SphericalSurface.h
@@ -1,8 +1,8 @@
+#pragma once
 
 #include "ParametricSurface.h"
 
-#ifndef _IRT_SPHERICAL_SURFACE_
-#define _IRT_SPHERICAL_SURFACE_
+namespace IRT2 {
 
 class SphericalSurface: public ParametricSurface {
  public:
@@ -48,4 +48,4 @@ class SphericalSurface: public ParametricSurface {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/ToricSurface.h b/include/ToricSurface.h
index a5a599d..88eefe7 100644
--- a/include/ToricSurface.h
+++ b/include/ToricSurface.h
@@ -1,3 +1,4 @@
+#pragma once
 
 #include "ParametricSurface.h"
 
@@ -8,8 +9,7 @@
 // in 3D ends up with a quartic equation);
 //
 
-#ifndef _IRT_TORIC_SURFACE_
-#define _IRT_TORIC_SURFACE_
+namespace IRT2 {
 
 class ToricSurface: public ParametricSurface {
  public:
@@ -104,4 +104,4 @@ class ToricSurface: public ParametricSurface {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/include/TransientParticle.h b/include/TransientParticle.h
index d4f4cab..14d982c 100644
--- a/include/TransientParticle.h
+++ b/include/TransientParticle.h
@@ -1,9 +1,9 @@
+#pragma once
 
 #include <TObject.h>
 #include <TVector3.h>
 
-#ifndef _TRANSIENT_PARTICLE_
-#define _TRANSIENT_PARTICLE_
+namespace IRT2 {
 
 // Need a separate class because do not want to deal with G4VUserTrackInformation serialization;
 class TransientParticle: public TObject {
@@ -38,4 +38,4 @@ class TransientParticle: public TObject {
 #endif
 };
 
-#endif
+} // namespace IRT2
diff --git a/source/Calibration.cc b/source/Calibration.cc
index 2797531..583aca8 100644
--- a/source/Calibration.cc
+++ b/source/Calibration.cc
@@ -7,6 +7,8 @@
 #include "Calibration.h"
 #include "CherenkovDetectorCollection.h"
 
+namespace IRT2 {
+
 // FIXME: yes, fix it please;
 static unsigned hdim = 100;
 static double hmin = -30.0, hmax = 30.0, hbin = (hmax - hmin)/hdim, hwnd = 15.0; 
@@ -378,3 +380,5 @@ void Calibration::ExportModifiedOpticsFile(const char *fname)
 } // Calibration::ExportModifiedOpticsFile()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/ChargedParticle.cc b/source/ChargedParticle.cc
index 55f3e0e..c92e382 100644
--- a/source/ChargedParticle.cc
+++ b/source/ChargedParticle.cc
@@ -11,6 +11,8 @@
 
 #include "ChargedParticle.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 double ChargedParticle::GetRecoCherenkovPhotonTheta(unsigned id)
@@ -92,3 +94,5 @@ unsigned ChargedParticle::GetRecoCherenkovPhotonCount(CherenkovRadiator *radiato
 } // ChargedParticle::GetRecoCherenkovPhotonCount()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/CherenkovRadiator.cc b/source/CherenkovRadiator.cc
index 480f4b3..0b3d423 100644
--- a/source/CherenkovRadiator.cc
+++ b/source/CherenkovRadiator.cc
@@ -5,6 +5,8 @@
 
 #include "CherenkovRadiator.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 CherenkovRadiatorPlots::CherenkovRadiatorPlots(const char *tag):
@@ -85,3 +87,5 @@ void CherenkovRadiator::DisplayStandardPlots(const char *cname, int wtopx,
 } // CherenkovRadiator::DisplayStandardPlots()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/ConicalSurface.cc b/source/ConicalSurface.cc
index 733d645..29714a2 100644
--- a/source/ConicalSurface.cc
+++ b/source/ConicalSurface.cc
@@ -3,6 +3,8 @@
 
 #include "ConicalSurface.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 bool ConicalSurface::GetCrossing(const TVector3 &x0, const TVector3 &n0, TVector3 *crs, 
@@ -30,3 +32,5 @@ double ConicalSurface::GetDistance(const TVector3 &xx) const
 } // ConicalSurface::GetDistance()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/CylindricalSurface.cc b/source/CylindricalSurface.cc
index 592f4d8..78d5fa5 100644
--- a/source/CylindricalSurface.cc
+++ b/source/CylindricalSurface.cc
@@ -3,6 +3,8 @@
 
 #include "CylindricalSurface.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 bool CylindricalSurface::GetCrossing(const TVector3 &x0, const TVector3 &n0, TVector3 *crs, 
@@ -27,3 +29,5 @@ double CylindricalSurface::GetDistance(const TVector3 &xx) const
 } // CylindricalSurface::GetDistance()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/Digitization.cc b/source/Digitization.cc
index 9418a58..6b022cd 100644
--- a/source/Digitization.cc
+++ b/source/Digitization.cc
@@ -6,6 +6,8 @@
 #include "GeantImport.h"
 #include "Digitization.h"
 
+namespace IRT2 {
+
 // Kind of digitization; may want to comment out (or set very fine) for debugging;
 #define _SENSOR_ACTIVE_AREA_PIXELLATION_DEFAULT_      (32)
 
@@ -156,3 +158,5 @@ void Digitization::ProduceDigitizedHits(bool calibration)
 } // Digitization::ProduceDigitizedHits()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/DigitizedHit.cc b/source/DigitizedHit.cc
index ef0bf99..5b59887 100644
--- a/source/DigitizedHit.cc
+++ b/source/DigitizedHit.cc
@@ -1,7 +1,10 @@
 
 #include "DigitizedHit.h"
 
+namespace IRT2 {
 
 // -------------------------------------------------------------------------------------
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/FlatSurface.cc b/source/FlatSurface.cc
index a6ab38c..1910a4c 100644
--- a/source/FlatSurface.cc
+++ b/source/FlatSurface.cc
@@ -1,6 +1,8 @@
 
 #include "FlatSurface.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 bool FlatSurface::GetCrossing(const TVector3 &x0, const TVector3 &n0, TVector3 *crs, 
@@ -35,3 +37,5 @@ double FlatSurface::GetDistance(const TVector3 &xx) const
 } // FlatSurface::GetDistance()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/GeantImport.cc b/source/GeantImport.cc
index 7ba93d0..2256d15 100644
--- a/source/GeantImport.cc
+++ b/source/GeantImport.cc
@@ -5,6 +5,8 @@
 #include "CherenkovEvent.h"
 #include "GeantImport.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 GeantImport::GeantImport(const char *dfname, const char *cfname, const char *dname):
@@ -50,3 +52,5 @@ void GeantImport::GetInputTreeEntry(unsigned ev) const
 } // GeantImport::GetInputTreeEntry()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/IRT.cc b/source/IRT.cc
index 2ff4c46..3ceb0e1 100644
--- a/source/IRT.cc
+++ b/source/IRT.cc
@@ -1,6 +1,8 @@
 
 #include "IRT.h"
 
+namespace IRT2 {
+
 thread_local TVector3 OpticalBoundary::m_ImpactPoint, OpticalBoundary::m_IncomingDirection;
 thread_local TVector3 OpticalBoundary::m_OutgoingDirection;
 
@@ -224,3 +226,5 @@ IRTSolution IRT::Solve(const TVector3 &xfrom, const TVector3 &nfrom, const doubl
 } // IRT::Solve()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/ParametricSurface.cc b/source/ParametricSurface.cc
index 1f00aae..8bee3d4 100644
--- a/source/ParametricSurface.cc
+++ b/source/ParametricSurface.cc
@@ -1,6 +1,8 @@
 
 #include "ParametricSurface.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 bool ParametricSurface::GetQuadraticEquationCaseCrossing(const TVector3 &x0, const TVector3 &n0, 
@@ -34,3 +36,5 @@ bool ParametricSurface::GetQuadraticEquationCaseCrossing(const TVector3 &x0, con
 } // ParametricSurface::GetQuadraticEquationCaseCrossing()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/ReconstructionFactory.cc b/source/ReconstructionFactory.cc
index 497e038..44665c2 100644
--- a/source/ReconstructionFactory.cc
+++ b/source/ReconstructionFactory.cc
@@ -18,6 +18,8 @@
 #include "CherenkovEvent.h"
 #include "ReconstructionFactory.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 ReconstructionFactory::ReconstructionFactory(const char *dfname, const char *cfname, 
@@ -617,3 +619,5 @@ void ReconstructionFactory::DisplayStandardPlots(const char *cname, int wtopx,
 } // ReconstructionFactory::DisplayStandardPlots()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/SphericalSurface.cc b/source/SphericalSurface.cc
index f02c1c6..5e5f26d 100644
--- a/source/SphericalSurface.cc
+++ b/source/SphericalSurface.cc
@@ -1,6 +1,8 @@
 
 #include "SphericalSurface.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 bool SphericalSurface::GetCrossing(const TVector3 &x0, const TVector3 &n0, TVector3 *crs, 
@@ -20,3 +22,5 @@ double SphericalSurface::GetDistance(const TVector3 &xx) const
 } // SphericalSurface::GetDistance()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2
diff --git a/source/ToricSurface.cc b/source/ToricSurface.cc
index 8ca2d7b..63d6acc 100644
--- a/source/ToricSurface.cc
+++ b/source/ToricSurface.cc
@@ -1,6 +1,8 @@
 
 #include "ToricSurface.h"
 
+namespace IRT2 {
+
 // -------------------------------------------------------------------------------------
 
 bool ToricSurface::GetCrossing(const TVector3 &x0, const TVector3 &n0, TVector3 *crs, 
@@ -30,3 +32,5 @@ double ToricSurface::GetDistance(const TVector3 &xx) const
 } // ToricSurface::GetDistance()
 
 // -------------------------------------------------------------------------------------
+
+} // namespace IRT2