diff --git a/ufw-docker b/ufw-docker
index 134926a..a081ee6 100755
--- a/ufw-docker
+++ b/ufw-docker
@@ -2,6 +2,9 @@
 set -euo pipefail
 [[ -n "${DEBUG:-}" ]] && set -x
 
+LANG=en_US.UTF-8
+LANGUAGE=en_US:
+LC_ALL=en_US.UTF-8
 PATH="/bin:/usr/bin:/sbin:/usr/sbin"
 
 GREP_REGEXP_INSTANCE_NAME="[-_.[:alnum:]]\\+"