diff --git a/tests/helpers/test_initialize_mth5.py b/tests/helpers/test_initialize_mth5.py
index b9ba42b0..ad5cc1f4 100644
--- a/tests/helpers/test_initialize_mth5.py
+++ b/tests/helpers/test_initialize_mth5.py
@@ -51,6 +51,33 @@ def tearDownClass(self):
         self.wd.joinpath("test.h5").unlink()
 
 
+
+class TestCompression(unittest.TestCase):
+    @classmethod
+    def setUpClass(self):
+        self.wd = Path().cwd()
+
+
+    def test_has_open_file(self):
+        self.m = initialize_mth5(self.wd.joinpath("test.h5"), "w")
+        self.assertIsInstance(self.m, MTH5)
+
+    def test_validate_compression(self):
+        """        COMPRESSION = ["lzf", "gzip", "szip", None]"""
+        from mth5.helpers import COMPRESSION
+        from mth5.helpers import COMPRESSION_LEVELS
+        for compression_type in COMPRESSION:
+            for compression_level in COMPRESSION_LEVELS[compression_type]:
+                self.m = MTH5(compression=compression_type, compression_opts=compression_level)
+                self.m.open_mth5(self.wd.joinpath("test.h5"), mode="a")
+                self.m = initialize_mth5(self.wd.joinpath("test.h5"), "w")
+                self.assertIsInstance(self.m, MTH5)
+                self.m.close_mth5()
+
+    @classmethod
+    def tearDownClass(self):
+        close_open_files()
+        self.wd.joinpath("test.h5").unlink()
 # =============================================================================
 # Run
 # =============================================================================