diff --git a/scripts/build_industrial_distribution_key.py b/scripts/build_industrial_distribution_key.py
index b86d47c2..e6d515b0 100644
--- a/scripts/build_industrial_distribution_key.py
+++ b/scripts/build_industrial_distribution_key.py
@@ -130,7 +130,7 @@ def build_nodal_distribution_key(hotmaps, regions, countries):
 
         if not facilities.empty:
             emissions = facilities["Emissions_ETS_2014"].fillna(
-                hotmaps["Emissions_EPRTR_2014"]
+                hotmaps["Emissions_EPRTR_2014"].dropna()
             )
             if emissions.sum() == 0:
                 key = pd.Series(1 / len(facilities), facilities.index)