diff --git a/bin/slurm_calibrate.sh b/bin/slurm_calibrate.sh
index 721edbbe3b8978494a19a2823b23c04d8716482b..a600fa7eaf2e97da42144b7c9a213f66cb9cadc3 100755
--- a/bin/slurm_calibrate.sh
+++ b/bin/slurm_calibrate.sh
@@ -28,8 +28,8 @@ export CAL_NOTEBOOK_NAME="$notebook"
 # make sure we use agg backend
 export MPLBACKEND=AGG
 
-# Ensure Python uses UTF-8 for files by default
-export LANG=en_US.UTF-8
+# Use the default locale (Python will still use UTF-8 for text files)
+export LANG=C
 
 # start an ip cluster if requested
 if [ "${ipcluster_profile}" != "NO_CLUSTER" ]