diff --git a/spectrum_fundamentals/constants.py b/spectrum_fundamentals/constants.py
index cd8644c..ce4115c 100644
--- a/spectrum_fundamentals/constants.py
+++ b/spectrum_fundamentals/constants.py
@@ -244,6 +244,7 @@
     "MASS_ANALYZER",
     "FRAGMENTATION",
     "COLLISION_ENERGY",
+    "INSTRUMENT_TYPES"
 ]
 MZML_DATA_COLUMNS = SHARED_DATA_COLUMNS + MZML_ONLY_DATA_COLUMNS