diff --git a/src/cell.cpp b/src/cell.cpp
index 844246f64d..798935358f 100644
--- a/src/cell.cpp
+++ b/src/cell.cpp
@@ -14,6 +14,17 @@
 
 namespace openmc {
 
+//==============================================================================
+// Constants
+//==============================================================================
+
+// TODO: Convert to enum
+constexpr int32_t OP_LEFT_PAREN   {std::numeric_limits<int32_t>::max()};
+constexpr int32_t OP_RIGHT_PAREN  {std::numeric_limits<int32_t>::max() - 1};
+constexpr int32_t OP_COMPLEMENT   {std::numeric_limits<int32_t>::max() - 2};
+constexpr int32_t OP_INTERSECTION {std::numeric_limits<int32_t>::max() - 3};
+constexpr int32_t OP_UNION        {std::numeric_limits<int32_t>::max() - 4};
+
 //==============================================================================
 // Global variables
 //==============================================================================
diff --git a/src/cell.h b/src/cell.h
index 4aa7c15c30..0b42a656c3 100644
--- a/src/cell.h
+++ b/src/cell.h
@@ -24,13 +24,6 @@ extern "C" int FILL_MATERIAL;
 extern "C" int FILL_UNIVERSE;
 extern "C" int FILL_LATTICE;
 
-// TODO: Convert to enum
-constexpr int32_t OP_LEFT_PAREN   {std::numeric_limits<int32_t>::max()};
-constexpr int32_t OP_RIGHT_PAREN  {std::numeric_limits<int32_t>::max() - 1};
-constexpr int32_t OP_COMPLEMENT   {std::numeric_limits<int32_t>::max() - 2};
-constexpr int32_t OP_INTERSECTION {std::numeric_limits<int32_t>::max() - 3};
-constexpr int32_t OP_UNION        {std::numeric_limits<int32_t>::max() - 4};
-
 //==============================================================================
 // Global variables
 //==============================================================================
diff --git a/src/distribution.cpp b/src/distribution.cpp
index 01255f2d75..f513701fb0 100644
--- a/src/distribution.cpp
+++ b/src/distribution.cpp
@@ -245,7 +245,7 @@ UPtrDist distribution_from_xml(pugi::xml_node node)
     openmc::fatal_error("Distribution type must be specified.");
 
   // Determine type of distribution
-  std::string type = get_node_value(node, "type");
+  std::string type = get_node_value(node, "type", true, true);
 
   // Allocate extension of Distribution
   if (type == "uniform") {
diff --git a/src/surface.cpp b/src/surface.cpp
index 94c24c82db..261a8d7d24 100644
--- a/src/surface.cpp
+++ b/src/surface.cpp
@@ -151,7 +151,7 @@ Surface::Surface(pugi::xml_node surf_node)
   }
 
   if (check_for_node(surf_node, "boundary")) {
-    std::string surf_bc = get_node_value(surf_node, "boundary");
+    std::string surf_bc = get_node_value(surf_node, "boundary", true, true);
 
     if (surf_bc == "transmission" || surf_bc == "transmit" ||surf_bc.empty()) {
       bc = BC_TRANSMIT;
@@ -1040,7 +1040,7 @@ read_surfaces(pugi::xml_node *node)
     int i_surf;
     for (surf_node = node->child("surface"), i_surf = 0; surf_node;
          surf_node = surf_node.next_sibling("surface"), i_surf++) {
-      std::string surf_type = get_node_value(surf_node, "type");
+      std::string surf_type = get_node_value(surf_node, "type", true, true);
 
       if (surf_type == "x-plane") {
         surfaces_c[i_surf] = new SurfaceXPlane(surf_node);
diff --git a/src/xml_interface.cpp b/src/xml_interface.cpp
index 7f3222a524..c89e19ef19 100644
--- a/src/xml_interface.cpp
+++ b/src/xml_interface.cpp
@@ -1,6 +1,6 @@
 #include "xml_interface.h"
 
-#include <algorithm>  // for std::transform
+#include <algorithm>  // for transform
 #include <sstream>
 
 #include "error.h"
@@ -9,10 +9,11 @@
 namespace openmc {
 
 std::string
-get_node_value_str(pugi::xml_node node, const char* name)
+get_node_value(pugi::xml_node node, const char* name, bool lowercase,
+               bool strip)
 {
   // Search for either an attribute or child tag and get the data as a char*.
-  const pugi::char_t *value_char;
+  const pugi::char_t* value_char;
   if (node.attribute(name)) {
     value_char = node.attribute(name).value();
   } else if (node.child(name)) {
@@ -23,20 +24,18 @@ get_node_value_str(pugi::xml_node node, const char* name)
             << node.name() << "\" XML node";
     fatal_error(err_msg);
   }
-  return value_char;
-}
+  std::string value {value_char};
 
+  // Convert to lower-case if needed
+  if (lowercase) {
+    std::transform(value.begin(), value.end(), value.begin(), ::tolower);
+  }
 
-std::string
-get_node_value(pugi::xml_node node, const char *name)
-{
-  // Get char* and convert to lowercase string.
-  std::string value {get_node_value_str(node, name)};
-  std::transform(value.begin(), value.end(), value.begin(), ::tolower);
-
-  // Remove whitespace.
-  value.erase(0, value.find_first_not_of(" \t\r\n"));
-  value.erase(value.find_last_not_of(" \t\r\n") + 1);
+  // Strip leading/trailing whitespace if needed
+  if (strip) {
+    value.erase(0, value.find_first_not_of(" \t\r\n"));
+    value.erase(value.find_last_not_of(" \t\r\n") + 1);
+  }
 
   return value;
 }
diff --git a/src/xml_interface.h b/src/xml_interface.h
index b12e6185b6..f10143697a 100644
--- a/src/xml_interface.h
+++ b/src/xml_interface.h
@@ -16,14 +16,14 @@ check_for_node(pugi::xml_node node, const char *name)
   return node.attribute(name) || node.child(name);
 }
 
-std::string get_node_value_str(pugi::xml_node node, const char *name);
-std::string get_node_value(pugi::xml_node node, const char *name);
+std::string get_node_value(pugi::xml_node node, const char *name,
+  bool lowercase=false, bool strip=false);
 
 template <typename T>
 std::vector<T> get_node_array(pugi::xml_node node, const char* name)
 {
   // Get value of node attribute/child
-  std::string s {get_node_value_str(node, name)};
+  std::string s {get_node_value(node, name)};
 
   // Read values one by one into vector
   std::stringstream iss {s};