diff --git a/tests/interp_mod_grib1.F90 b/tests/interp_mod_grib1.F90
index 2259a773..6e6be145 100644
--- a/tests/interp_mod_grib1.F90
+++ b/tests/interp_mod_grib1.F90
@@ -100,6 +100,16 @@ subroutine interp(grid, interp_opt)
     data grd218 /3, 614, 428, 12190, -133459, 8, -95000,  &
          12191, 12191, 0, 64, 25000, 25000, 0, 0, 0, 0, 0, 0, 255, 180*0/
 
+#if (LSIZE==D)
+    abstol=0.0001
+#elif (LSIZE==4)
+    if ((trim(grid).eq."212") .and. (interp_opt.eq."6")) then
+        abstol=0.2
+    else
+        abstol=0.05
+    endif
+#endif
+
     select case (trim(grid))
     case ('3')
        output_kgds = grd3
@@ -242,7 +252,7 @@ subroutine interp(grid, interp_opt)
         do j = 1, j_output
            do i = 1, i_output
               output_data4 = real(output_data(i,j),4)
-              if ( abs(output_data4 - baseline_data(i,j)) > 0.0001) then
+              if ( abs(output_data4 - baseline_data(i,j)) > abstol) then
                  avgdiff = avgdiff + abs(output_data4-baseline_data(i,j))
                  num_pts_diff = num_pts_diff + 1
                  if (abs(output_data4-baseline_data(i,j)) > abs(maxdiff))then
@@ -370,6 +380,16 @@ subroutine interp_vector(grid, interp_opt)
     data grd218 /3, 614, 428, 12190, -133459, 8, -95000,  &
          12191, 12191, 0, 64, 25000, 25000, 0, 0, 0, 0, 0, 0, 255, 180*0/
 
+#if (LSIZE==D)
+    abstol=0.0001
+#elif (LSIZE==4)
+    if ((trim(grid).eq."212") .and. (interp_opt.eq."6")) then
+        abstol=0.2
+    else
+        abstol=0.05
+    endif
+#endif
+
     select case (trim(grid))
     case ('3')
        output_kgds = grd3
@@ -539,7 +559,7 @@ subroutine interp_vector(grid, interp_opt)
         do j = 1, j_output
            do i = 1, i_output
               output_data4 = real(output_u_data(i,j),4)
-              if (abs(output_data4 - baseline_u_data(i,j)) > 0.0001) then
+              if (abs(output_data4 - baseline_u_data(i,j)) > abstol) then
                  avg_u_diff = avg_u_diff + abs(output_data4-baseline_u_data(i,j))
                  num_upts_diff = num_upts_diff + 1
                  if (abs(output_data4-baseline_u_data(i,j)) > abs(max_u_diff))then
@@ -547,7 +567,7 @@ subroutine interp_vector(grid, interp_opt)
                  endif
               endif
               output_data4 = real(output_v_data(i,j),4)
-              if (abs(output_data4 - baseline_v_data(i,j)) > 0.0001) then
+              if (abs(output_data4 - baseline_v_data(i,j)) > abstol) then
                  avg_v_diff = avg_v_diff + abs(output_data4-baseline_v_data(i,j))
                  num_vpts_diff = num_vpts_diff + 1
                  if (abs(output_data4-baseline_v_data(i,j)) > abs(max_v_diff))then