diff --git a/modules/util/acspo_validate.py b/modules/util/acspo_validate.py
index 3850efedad64d5bdbb8911dc6377f1373850fce7..81e7878d4ef8715975d6d55464b32e550c9e1e69 100644
--- a/modules/util/acspo_validate.py
+++ b/modules/util/acspo_validate.py
@@ -37,7 +37,7 @@ def acspo_validate(oper_file, cspp_file, rel_tol=0.001, outfile_nc=None):
     start_idx_cspp, stop_idx_cspp = -1, -1
 
     for k in range(len(cntr_lat_oper)):
-        c_a = np.logical_and(np.isclose(cntr_lat_oper[k], cntr_lat_cspp), np.isclose(cntr_lon_oper[k], cntr_lon_cspp))
+        c_a = np.logical_and(np.isclose(cntr_lat_oper[k], cntr_lat_cspp, rtol=rel_tol), np.isclose(cntr_lon_oper[k], cntr_lon_cspp, rtol=rel_tol))
         if np.size(np.nonzero(c_a)[0]) == 1:
             if start_idx_oper == -1:
                 start_idx_oper = k