diff --git a/sources/user_problem.F90 b/sources/user_problem.F90
index 263376b..df938a4 100644
--- a/sources/user_problem.F90
+++ b/sources/user_problem.F90
@@ -1279,7 +1279,14 @@ module user_problem
 !
     crit = 0.0e+00
 
-    if (min(abs(pdata%meta%ymin), abs(pdata%meta%ymax)) <= yref) crit = 1.0e+00
+    if (pdata%meta%ymin <= 0.0d+00 .and. 0.0d+00 <= pdata%meta%ymax) then
+      crit = 1.0e+00
+      return
+    end if
+    if (abs(pdata%meta%ymin) <= yref .or. abs(pdata%meta%ymax) <= yref) then
+      crit = 1.0e+00
+      return
+    end if
 
     return