diff --git a/tests/rt.sh b/tests/rt.sh
index 3276e14719..ff08474b0a 100755
--- a/tests/rt.sh
+++ b/tests/rt.sh
@@ -778,7 +778,7 @@ case ${MACHINE_ID} in
     COMPILE_QUEUE="batch"
 
     PARTITION=
-    dprefix="/collab1/data/$USER"
+    dprefix="/collab1/data/${USER}"
     DISKNM="/collab1/data/Cameron.Book/UFS-WM_RT"
     STMP="${STMP:-${dprefix}/RT_BASELINE}"
     PTMP="${PTMP:-${dprefix}/RT_RUNDIRS}"