diff --git a/.gitea/workflows/build_and_test.yml b/.gitea/workflows/build_and_test.yml
index 8736c0b5..1b917ea3 100644
--- a/.gitea/workflows/build_and_test.yml
+++ b/.gitea/workflows/build_and_test.yml
@@ -141,7 +141,11 @@ jobs:
         run: |
           locale -a
           echo "LANG=$LANG LC_ALL=$LC_ALL"
+          export LANG=C.UTF-8
+          export LC_ALL=C.UTF-8
           source /opt/dials-v3-27-0/dials_env.sh
+          export LANG=C.UTF-8
+          export LC_ALL=C.UTF-8
           mkdir -p dials_test
           cd dials_test
           ../build/tools/jfjoch_hdf5_test ../tests/test_data/compression_benchmark.h5 100