diff --git a/check_mail_eklig.sh b/check_mail_eklig.sh
index 987e25f..c96cce5 100755
--- a/check_mail_eklig.sh
+++ b/check_mail_eklig.sh
@@ -8,7 +8,7 @@ prev_num=$(cat $PERSISTENCE_FILE)
 EXITCODE=3
 STATUS=UNKNOWN
 
-if [ $cur_num -gt $prev_num ]; then
+if [ "$cur_num" -gt "$prev_num" ]; then
     EXITCODE=0
     STATUS="OK: increasing"
 else