diff --git a/tests/gts_compare.sh b/tests/gts_compare.sh
index 0928aa3bb..88d3d899c 100755
--- a/tests/gts_compare.sh
+++ b/tests/gts_compare.sh
@@ -10,24 +10,18 @@
 
 . ./include.ctest.sh
 
-#set -x
-
-#Enter data dir
+# Enter data dir
 cd ${data_dir}/gts
 
-#Define a common label for all the tmp files
+# Define a common label for all the tmp files
 label="gts_compare_test"
 
-#Create log file
 fLog=${label}".log"
 rm -f $fLog
 touch $fLog
 
-#Define tmp GTS file
 fGtsTmp=${label}".gts.tmp"
 fRules=${label}".filt"
-fBufrInput1=${label}".bufr.input1"
-fBufrInput2=${label}".bufr.input2"
 
 #----------------------------------------------------
 # Test: comparing same files
@@ -61,7 +55,14 @@ rm -f error1_1.gts error2_1.gts
 #----------------------------------------------------
 # Test: comparing with and without the -b switch
 #----------------------------------------------------
-${tools_dir}/gts_compare -b GG $gts_file $fGtsTmp >> $fLog
+# Add wrong blocklist. Should still fail
+set +e
+${tools_dir}/gts_compare -b CCCC $gts_file $fGtsTmp
+status=$?
+set -e
+[ $status -eq 1 ]
+# Add correct blocklist
+${tools_dir}/gts_compare -b GG $gts_file $fGtsTmp
 
-#Clean up
+# Clean up
 rm -f $fLog $fGtsTmp $fRules
diff --git a/tests/metar_compare.sh b/tests/metar_compare.sh
index a42b84a92..dd662dab7 100755
--- a/tests/metar_compare.sh
+++ b/tests/metar_compare.sh
@@ -53,6 +53,13 @@ rm -f error1_1.metar error2_1.metar error1_2.metar error2_2.metar
 #----------------------------------------------------
 # Test: comparing with and without the -b switch
 #----------------------------------------------------
+# Add wrong blocklist. Should still fail
+set +e
+${tools_dir}/metar_compare -b CCCC $metar_file $fMetarTmp
+status=$?
+set -e
+[ $status -eq 1 ]
+# Add correct blocklist
 ${tools_dir}/metar_compare -b minute,theMessage $metar_file $fMetarTmp
 
 #Clean up