diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9facdf7ba..e62c41347 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -423,6 +423,7 @@ add_library(libopenmc SHARED
   src/nuclide.cpp
   src/output.cpp
   src/particle.cpp
+  src/physics_common.cpp
   src/plot.cpp
   src/position.cpp
   src/pugixml/pugixml_c.cpp
diff --git a/include/openmc/physics_common.h b/include/openmc/physics_common.h
new file mode 100644
index 000000000..33fb8ed61
--- /dev/null
+++ b/include/openmc/physics_common.h
@@ -0,0 +1,16 @@
+//! \file physics_common.h
+//! A collection of physics methods common to MG, CE, photon, etc.
+
+#ifndef OPENMC_PHYSICS_COMMON_H
+#define OPENMC_PHYSICS_COMMON_H
+
+#include "openmc/particle.h"
+
+namespace openmc {
+
+//! \brief Performs the russian roulette operation for a particle
+extern "C" void
+russian_roulette(Particle* p);
+
+} // namespace openmc
+#endif // OPENMC_PHYSICS_COMMON_H
diff --git a/src/physics_common.F90 b/src/physics_common.F90
index 63bf62ce6..0d5b9fb32 100644
--- a/src/physics_common.F90
+++ b/src/physics_common.F90
@@ -1,33 +1,20 @@
 module physics_common
 
-  use constants
+  use, intrinsic :: ISO_C_BINDING
+
   use particle_header,        only: Particle
-  use random_lcg,             only: prn
-  use settings,               only: weight_cutoff, weight_survive
 
   implicit none
 
-contains
-
 !===============================================================================
-! RUSSIAN_ROULETTE
+! RUSSIAN_ROULETTE FROM C
 !===============================================================================
 
-  subroutine russian_roulette(p)
-
-    type(Particle), intent(inout) :: p
-
-    if (p % wgt < weight_cutoff) then
-      if (prn() < p % wgt / weight_survive) then
-        p % wgt = weight_survive
-        p % last_wgt = p % wgt
-      else
-        p % wgt = ZERO
-        p % last_wgt = ZERO
-        p % alive = .false.
-      end if
-    end if
-
-  end subroutine russian_roulette
+  interface
+    subroutine russian_roulette(p) bind(C)
+      import Particle
+      type(Particle), intent(inout) :: p
+    end subroutine russian_roulette
+  end interface
 
 end module physics_common
diff --git a/src/physics_common.cpp b/src/physics_common.cpp
new file mode 100644
index 000000000..02c77ae7d
--- /dev/null
+++ b/src/physics_common.cpp
@@ -0,0 +1,26 @@
+#include "openmc/physics_common.h"
+
+#include "openmc/settings.h"
+#include "openmc/random_lcg.h"
+
+namespace openmc {
+
+//==============================================================================
+// RUSSIAN_ROULETTE
+//==============================================================================
+
+void russian_roulette(Particle* p)
+{
+  if (p->wgt < settings::weight_cutoff) {
+    if (prn() < p->wgt / settings::weight_survive) {
+      p->wgt = settings::weight_survive;
+      p->last_wgt = p->wgt;
+    } else {
+      p->wgt = 0.;
+      p->last_wgt = 0.;
+      p->alive = false;
+    }
+  }
+}
+
+} //namespace openmc