diff --git a/protozfits/tests/test_R1_example_file.py b/protozfits/tests/test_R1_example_file.py
index f6cd53f..6ee13c9 100644
--- a/protozfits/tests/test_R1_example_file.py
+++ b/protozfits/tests/test_R1_example_file.py
@@ -15,7 +15,8 @@
 
 def test_can_open_file():
     from protozfits import SimpleFile
-    SimpleFile(example_file_path)
+    f = SimpleFile(example_file_path)
+    f.close()
 
 
 def test_can_iterate_over_events_and_run_header():
@@ -30,3 +31,11 @@ def test_can_iterate_over_events_and_run_header():
         assert event.pixel_status.shape == (14,)
         assert event.lstcam.first_capacitor_id.shape == (16,)
         assert event.lstcam.counters.shape == (44,)
+    f.close()
+
+def test_event_ids():
+    from protozfits import SimpleFile
+    with SimpleFile(example_file_path) as f:
+        event_ids = [e.event_id for e in f.Events]
+
+    assert (np.array(event_ids) == 1 + np.arange(len(event_ids))).all()