diff --git a/src/surface.cpp b/src/surface.cpp
index 9361fa4241..f329fda6d2 100644
--- a/src/surface.cpp
+++ b/src/surface.cpp
@@ -4,7 +4,6 @@
 #include <cmath>
 #include <sstream>
 #include <utility>
-#include <ciso646>
 
 #include "openmc/error.h"
 #include "openmc/hdf5_interface.h"
@@ -298,7 +297,7 @@ template<int i> double
 axis_aligned_plane_distance(Position r, Direction u, bool coincident, double offset)
 {
   const double f = offset - r[i];
-  if (coincident or std::abs(f) < FP_COINCIDENT or u[i] == 0.0) return INFTY;
+  if (coincident || std::abs(f) < FP_COINCIDENT || u[i] == 0.0) return INFTY;
   const double d = f / u[i];
   if (d < 0.0) return INFTY;
   return d;
@@ -494,7 +493,7 @@ SurfacePlane::distance(Position r, Direction u, bool coincident) const
 {
   const double f = A_*r.x + B_*r.y + C_*r.z - D_;
   const double projection = A_*u.x + B_*u.y + C_*u.z;
-  if (coincident or std::abs(f) < FP_COINCIDENT or projection == 0.0) {
+  if (coincident || std::abs(f) < FP_COINCIDENT || projection == 0.0) {
     return INFTY;
   } else {
     const double d = -f / projection;
@@ -574,7 +573,7 @@ axis_aligned_cylinder_distance(Position r, Direction u,
     // No intersection with cylinder.
     return INFTY;
 
-  } else if (coincident or std::abs(c) < FP_COINCIDENT) {
+  } else if (coincident || std::abs(c) < FP_COINCIDENT) {
     // Particle is on the cylinder, thus one distance is positive/negative
     // and the other is zero. The sign of k determines if we are facing in or
     // out.
@@ -744,7 +743,7 @@ double SurfaceSphere::distance(Position r, Direction u, bool coincident) const
     // No intersection with sphere.
     return INFTY;
 
-  } else if (coincident or std::abs(c) < FP_COINCIDENT) {
+  } else if (coincident || std::abs(c) < FP_COINCIDENT) {
     // Particle is on the sphere, thus one distance is positive/negative and
     // the other is zero. The sign of k determines if we are facing in or out.
     if (k >= 0.0) {
@@ -821,7 +820,7 @@ axis_aligned_cone_distance(Position r, Direction u,
     // No intersection with cone.
     return INFTY;
 
-  } else if (coincident or std::abs(c) < FP_COINCIDENT) {
+  } else if (coincident || std::abs(c) < FP_COINCIDENT) {
     // Particle is on the cone, thus one distance is positive/negative
     // and the other is zero. The sign of k determines if we are facing in or
     // out.
@@ -1009,7 +1008,7 @@ SurfaceQuadric::distance(Position r, Direction ang, bool coincident) const
     // No intersection with surface.
     return INFTY;
 
-  } else if (coincident or std::abs(c) < FP_COINCIDENT) {
+  } else if (coincident || std::abs(c) < FP_COINCIDENT) {
     // Particle is on the surface, thus one distance is positive/negative and
     // the other is zero. The sign of k determines which distance is zero and
     // which is not.
@@ -1156,27 +1155,27 @@ void read_surfaces(pugi::xml_node node)
 
       // See if this surface makes part of the global bounding box.
       BoundingBox bb = surf->bounding_box();
-      if (bb.xmin > -INFTY and bb.xmin < xmin) {
+      if (bb.xmin > -INFTY && bb.xmin < xmin) {
         xmin = bb.xmin;
         i_xmin = i_surf;
       }
-      if (bb.xmax < INFTY and bb.xmax > xmax) {
+      if (bb.xmax < INFTY && bb.xmax > xmax) {
         xmax = bb.xmax;
         i_xmax = i_surf;
       }
-      if (bb.ymin > -INFTY and bb.ymin < ymin) {
+      if (bb.ymin > -INFTY && bb.ymin < ymin) {
         ymin = bb.ymin;
         i_ymin = i_surf;
       }
-      if (bb.ymax < INFTY and bb.ymax > ymax) {
+      if (bb.ymax < INFTY && bb.ymax > ymax) {
         ymax = bb.ymax;
         i_ymax = i_surf;
       }
-      if (bb.zmin > -INFTY and bb.zmin < zmin) {
+      if (bb.zmin > -INFTY && bb.zmin < zmin) {
         zmin = bb.zmin;
         i_zmin = i_surf;
       }
-      if (bb.zmax < INFTY and bb.zmax > zmax) {
+      if (bb.zmax < INFTY && bb.zmax > zmax) {
         zmax = bb.zmax;
         i_zmax = i_surf;
       }