diff --git a/pyreduce/instruments/common.py b/pyreduce/instruments/common.py
index 42eaec62..e6652b99 100644
--- a/pyreduce/instruments/common.py
+++ b/pyreduce/instruments/common.py
@@ -305,9 +305,10 @@ def add_header_info(self, header, mode, **kwargs):
         header["e_obslat"] = get("latitude")
         header["e_obsalt"] = get("altitude")
 
-        header["HIERARCH e_wavecal_element"] = get(
-            "wavecal_element", info.get("wavecal_element", None)
-        )
+        if info.get("wavecal_element", None) is not None:
+            header["HIERARCH e_wavecal_element"] = get(
+                "wavecal_element", info.get("wavecal_element", None)
+            )
         return header
 
     def find_files(self, input_dir):