Fire dampers shut automatically to prevent the propagation of fire and smoke through ductwork to adjacent designated fire compartments. FK-K90 fire dampers are tested according to DIN 4102 and
EN 1366-2. Local requirements and building inspectorate approvals are essential.

Correct approved installation locations are directly in solid walls, ceiling slabs, gypsum wall boards, lightweight partitions and lightweight fire walls, directly on the face of solid walls and ceiling slabs, adjacent to solid walls and ceiling slabs and remote from solid walls. Installation in vertical or horizontal ducts. Air flow direction is not critical. When installed in walls or ceiling slabs combustible ventilation ducting may be connected directly to the fire damper. In the case of fire, the damper is triggered at 72 °C or 95 °C (for use in warm air ventilation) either by a fusible link or thermoelectrically with a spring return actuator. The release mechanism is accessible and can be tested from the outside. The fire dampers have two inspection panels.

The fire resistance class of fire dampers type FK-K90 is dependent on the application.