7/3/2024

Natural smoke and heat exhaust ventilators (NSHEV’s) are used to create an opening in the outer shell of a building. In case of a fire the NSHEV can be opened to extract the smoke from the building.

The operating principle of a NSHEV is based on the physical principle that warm air rises (stack- or chimney effect). Because the smoke is extracted from the building, a smoke free layer above the floor is created, which results in better conditions for people to escape from the building. Other additional benefits of the NSHEV are the reduction of fire and smoke damage, facilitation of firefighter access by improving visibility, reduction of roof temperatures and retardation of the lateral spread of fire.

To obtain these benefits it is essential that the NSHEV operates as intended and reliably in case of a fire. To determine this operability and reliability, NSHEV’s are tested according to EN 12101-2.   Efectis is used to test the fire performance of the NSHEV, notably according to annex G.. Annex G describes tests for opening under heat. For this test the NSHEV is mounted on a furnace and heated for a period of 30 minutes. After 5 minutes of heating the NSHEV is manually opened (right picture). This test is performed to determine the ability of the NSHEV to open when exposed to heat and retain its fire open position during a fire.

In recent months, in addition to fire performance tests, Efectis has carried out accredited tests according to appendix E of this standard on behalf of a German NSHEV manufacturer.

Annex E describes the test for opening at low ambient temperature with a simulated snow load. For these tests, the NSHEV was installed in a climatic chamber and loaded with a predetermined amount of weight bags. The test specimen was cooled down to -15°C before the NSHEV is opened three times into its fire open position (left picture). These tests are performed to determine the ability of the NSHEV to open during freezing winter temperatures and being covered with snow.

Efectis is notified for CE mark and is an approved body for UKCA mark dedicated to UK market.

For more information, please contact Anouk Burgstad