diff --git a/tests/ocean_merge/ftst_merge.F90 b/tests/ocean_merge/ftst_merge.F90
index f0d5b0ab2..6d9c40728 100644
--- a/tests/ocean_merge/ftst_merge.F90
+++ b/tests/ocean_merge/ftst_merge.F90
@@ -1,5 +1,7 @@
 ! Unit test for the merge routine.
-
+! 
+! Test several combinations of lake and ocean attributes
+! and check the 'merged' value for correctness.
  program ftst_merge
 
  implicit none
diff --git a/tests/ocean_merge/ftst_read_lake_mask.F90 b/tests/ocean_merge/ftst_read_lake_mask.F90
index e345607cc..3754455cc 100644
--- a/tests/ocean_merge/ftst_read_lake_mask.F90
+++ b/tests/ocean_merge/ftst_read_lake_mask.F90
@@ -1,6 +1,6 @@
 ! Unit test for the read_lake_mask routine.
 !
-! Reads a 6x4 version of the lake mask file and
+! Reads a 6x4 version of the lake mask NetCDF file and
 ! checks values from the lake fraction, lake depth
 ! and latitude records. If differences exceed a
 ! threshold, then the test fails.
diff --git a/tests/ocean_merge/ftst_read_nml.F90 b/tests/ocean_merge/ftst_read_nml.F90
index 3765c2b10..d10017e0c 100644
--- a/tests/ocean_merge/ftst_read_nml.F90
+++ b/tests/ocean_merge/ftst_read_nml.F90
@@ -1,5 +1,8 @@
 ! Unit test for the read_nml routine.
-
+!
+! Read a sample namelist and check the data in each
+! variable against expected values.
+!
  program read_namelist
 
  implicit none
@@ -19,8 +22,8 @@ program read_namelist
  if (trim(lake_mask_dir) /= "/lake/mask/dir") stop 4
  if (trim(atmres) /= "C96") stop 6
  if (trim(ocnres) /= "mx025") stop 8
- if (trim(out_dir) /= "/out/dir") stop 8
- if (binary_lake /= 1) stop 10
+ if (trim(out_dir) /= "/out/dir") stop 10
+ if (binary_lake /= 1) stop 12
 
  print*, "OK"
 
diff --git a/tests/ocean_merge/ftst_read_ocean_frac.F90 b/tests/ocean_merge/ftst_read_ocean_frac.F90
index ec35621ab..3e83377ed 100644
--- a/tests/ocean_merge/ftst_read_ocean_frac.F90
+++ b/tests/ocean_merge/ftst_read_ocean_frac.F90
@@ -1,6 +1,6 @@
 ! Unit test for the read_ocean_frac routine.
 !
-! Reads a 6x5 version of the ocean mask file and
+! Reads a 6x5 version of the MOM6 ocean mask file and
 ! checks values from the ocean fraction record.
 ! If differences exceed a threshold, then the test fails.
 !