diff --git a/modules/util/viirs.py b/modules/util/viirs.py
index 95fe0d245a7bba62dee4b55b83f219fcc74710bb..b83e4b7d9886babc3b520fdf0edc8930ee614308 100644
--- a/modules/util/viirs.py
+++ b/modules/util/viirs.py
@@ -1,6 +1,6 @@
 import numpy as np
 import h5py
-from util.util import get_grid_values
+from util.util import get_grid_values, get_grid_values_all
 import glob
 
 mod_res_params = ['M07', 'M08', 'M10', 'M12', 'M13', 'M14', 'M15', 'M16']
@@ -70,3 +70,14 @@ def run(mod_res_filename, img_res_filename, mod_tiles, img_tiles):
     img_h5f.close()
 
 
+def run_test(directory):
+    files = glob.glob(directory + 'clavrx_snpp_viirs*.h5')
+
+    for file in files:
+        h5f = h5py.File(file, 'r')
+        opd_nl = get_grid_values_all(h5f, 'cld_opd_nlcomp')
+        reff_nl = get_grid_values_all(h5f, 'cld_reff_nlcomp')
+
+        if np.sum(np.isnan(opd_nl)) < opd_nl.size and np.sum(np.isnan(reff_nl)) < reff_nl.size:
+            print(file)
+