diff --git a/generic3g/tests/Test_FixedLevelsVerticalGrid.pf b/generic3g/tests/Test_FixedLevelsVerticalGrid.pf
index 36ab5d58590f..2230f79c8217 100644
--- a/generic3g/tests/Test_FixedLevelsVerticalGrid.pf
+++ b/generic3g/tests/Test_FixedLevelsVerticalGrid.pf
@@ -30,5 +30,20 @@ contains
 
    end subroutine test_equals
    
+   @test
+   subroutine test_not_equals()
+      type(FixedLevelsVerticalGrid) :: vgrid1, vgrid2, vgrid3
+
+      real, parameter :: levels1(*) = [1.,5.,7.]
+      real, parameter :: levels2(*) = [.01,4.]
+
+      vgrid1 = FixedLevelsVerticalGrid(standard_name='air_pressure', units='Pa', levels=levels1)
+      vgrid2 = FixedLevelsVerticalGrid(standard_name='air_pressure', units='mb', levels=levels1)
+      vgrid3 = FixedLevelsVerticalGrid(standard_name='air_pressure', units='Pa', levels=levels2)
+      @assert_that(vgrid1 /= vgrid2, is(.true.))
+      @assert_that(vgrid1 /= vgrid3, is(.true.))
+
+   end subroutine test_not_equals
+   
    
 end module Test_FixedLevelsVerticalGrid
diff --git a/generic3g/vertical/FixedLevelsVerticalGrid.F90 b/generic3g/vertical/FixedLevelsVerticalGrid.F90
index 1727b2dc19a0..f0dac26777bf 100644
--- a/generic3g/vertical/FixedLevelsVerticalGrid.F90
+++ b/generic3g/vertical/FixedLevelsVerticalGrid.F90
@@ -91,17 +91,19 @@ logical function can_connect_to(this, src, rc)
        _UNUSED_DUMMY(src)
     end function can_connect_to
 
-    logical function equal_FixedLevelsVerticalGrid(a, b) result(equal)
+    impure elemental logical function equal_FixedLevelsVerticalGrid(a, b) result(equal)
        type(FixedLevelsVerticalGrid), intent(in) :: a, b
 
        equal = a%standard_name == b%standard_name
        if (.not. equal) return       
        equal = a%units == b%units
        if (.not. equal) return       
+       equal = size(a%levels) == size(b%levels)
+       if (.not. equal) return       
        equal = all(a%levels == b%levels)
     end function equal_FixedLevelsVerticalGrid 
 
-    logical function not_equal_FixedLevelsVerticalGrid(a, b) result(not_equal)
+    impure elemental logical function not_equal_FixedLevelsVerticalGrid(a, b) result(not_equal)
        type(FixedLevelsVerticalGrid), intent(in) :: a, b
 
        not_equal = .not. (a==b)