prEN 17020-2-2021 Extended application of test results on durability of self-closing for fire resistance and/or smoke control doorsets and openable windows - Part 2: Durability of self-closing of steel rolling shutters
2021prEN 17020-2-2021 Extended application of test results on durability of self-closing for fire resistance and/or smoke control doorsets and openable windows - Part 2: Durability of self-closing of steel rolling shutters