diff --git a/tests/test_demand.cpp b/tests/test_demand.cpp
index f39d8f7..52388aa 100644
--- a/tests/test_demand.cpp
+++ b/tests/test_demand.cpp
@@ -7,7 +7,7 @@
  Authors:      see AUTHORS
  Copyright:    see AUTHORS
  License:      see LICENSE
- Last Updated: 03/21/2019
+ Last Updated: 08/02/2023
  ******************************************************************************
 */
 
@@ -27,7 +27,9 @@ BOOST_AUTO_TEST_CASE(test_categories_save)
     EN_Project ph = NULL;
 
     error = EN_createproject(&ph);
+    BOOST_REQUIRE(error == 0);
     error = EN_open(ph, DATA_PATH_NET1, DATA_PATH_RPT, DATA_PATH_OUT);
+    BOOST_REQUIRE(error == 0);
 
     error = EN_getnodeindex(ph, (char *)"12", &Nindex);
     BOOST_REQUIRE(error == 0);
diff --git a/tests/test_overflow.cpp b/tests/test_overflow.cpp
index 5ad60a4..8c3e005 100644
--- a/tests/test_overflow.cpp
+++ b/tests/test_overflow.cpp
@@ -7,7 +7,7 @@
  Authors:      see AUTHORS
  Copyright:    see AUTHORS
  License:      see LICENSE
- Last Updated: 06/16/2019
+ Last Updated: 08/02/2023
  ******************************************************************************
 */
 
@@ -32,7 +32,9 @@ BOOST_AUTO_TEST_CASE(test_tank_overflow)
     EN_Project ph = NULL;
 
     error = EN_createproject(&ph);
+    BOOST_REQUIRE(error == 0);
     error = EN_open(ph, DATA_PATH_NET1, DATA_PATH_RPT, "");
+    BOOST_REQUIRE(error == 0);
 
     // Get index of the tank and its inlet/outlet pipe
     error = EN_getnodeindex(ph, (char *)"2", &Nindex);
diff --git a/tests/test_pda.cpp b/tests/test_pda.cpp
index b7c1636..6091def 100644
--- a/tests/test_pda.cpp
+++ b/tests/test_pda.cpp
@@ -7,7 +7,7 @@
  Authors:      see AUTHORS
  Copyright:    see AUTHORS
  License:      see LICENSE
- Last Updated: 07/20/2019
+ Last Updated: 08/02/2023
  ******************************************************************************
 */
 
@@ -30,7 +30,9 @@ BOOST_AUTO_TEST_CASE(test_pda_model)
 
     EN_Project ph = NULL;
     error = EN_createproject(&ph);
+    BOOST_REQUIRE(error == 0);
     error = EN_open(ph, DATA_PATH_NET1, DATA_PATH_RPT, "");
+    BOOST_REQUIRE(error == 0);
 
     // Set Demand Multiplier to 10 to cause negative pressures
     error = EN_setoption(ph, EN_DEMANDMULT, 10);