diff --git a/bacnet-stack/include/bacenum.h b/bacnet-stack/include/bacenum.h
index 54926683..7e36929f 100644
--- a/bacnet-stack/include/bacenum.h
+++ b/bacnet-stack/include/bacenum.h
@@ -825,6 +825,7 @@ typedef enum {
     UNITS_NANOGRAMS_PER_CUBIC_METER = 220,
     UNITS_GRAMS_PER_CUBIC_CENTIMETER = 221,
     UNITS_BECQUERELS = 222,
+    UNITS_KILOBECQUERELS = 223,
     UNITS_MEGABECQUERELS = 224,
     UNITS_GRAY = 225,
     UNITS_MILLIGRAY = 226,