diff --git a/BLAS/TESTING/cblat1.f b/BLAS/TESTING/cblat1.f
index f2f9b2126..09a704676 100644
--- a/BLAS/TESTING/cblat1.f
+++ b/BLAS/TESTING/cblat1.f
@@ -1033,6 +1033,8 @@ SUBROUTINE CB1NRM2(N,INCX,THRESH)
                ELSE
                   TRAT = ZERO
                END IF
+            ELSE IF (SNRM == ZNRM) THEN
+               TRAT = ZERO
             ELSE IF (ZNRM == ZERO) THEN
                TRAT = SNRM / ULP
             ELSE
diff --git a/BLAS/TESTING/zblat1.f b/BLAS/TESTING/zblat1.f
index 71438c420..bcdfa7b28 100644
--- a/BLAS/TESTING/zblat1.f
+++ b/BLAS/TESTING/zblat1.f
@@ -1033,6 +1033,8 @@ SUBROUTINE ZB1NRM2(N,INCX,THRESH)
                ELSE
                   TRAT = ZERO
                END IF
+            ELSE IF (SNRM == ZNRM) THEN
+               TRAT = ZERO
             ELSE IF (ZNRM == ZERO) THEN
                TRAT = SNRM / ULP
             ELSE