diff --git a/test_problems/NASA9poly_test/NASA9poly_test.cpp b/test_problems/NASA9poly_test/NASA9poly_test.cpp
index c74d78fb9..55a2acdcd 100644
--- a/test_problems/NASA9poly_test/NASA9poly_test.cpp
+++ b/test_problems/NASA9poly_test/NASA9poly_test.cpp
@@ -27,6 +27,7 @@ using namespace std;
 #include "kernel/TransportFactory.h"
 
 using namespace Cantera;
+using namespace Cantera_CXX;
 
 void printDbl(double val) {
   if (fabs(val) < 5.0E-17) {