diff --git a/src/frostfs_testlib/load/load_config.py b/src/frostfs_testlib/load/load_config.py
index 57e79f6..6f355fc 100644
--- a/src/frostfs_testlib/load/load_config.py
+++ b/src/frostfs_testlib/load/load_config.py
@@ -8,7 +8,7 @@ from typing import Any, Callable, Optional, get_args
 from frostfs_testlib.utils.converting_utils import calc_unit
 
 
-def convert_time_to_seconds(time: int | str) -> int:
+def convert_time_to_seconds(time: int | str | None) -> int:
     if time is None:
         return None
     if str(time).isdigit():