F-B90 Rectangular Fire Dampers

A multiblade fire damper and fire rated air transfer grille

  • Short body and no blade overhangs

  • Air transfer grille with cold smoke tightness

  • Duct connection from both sides always available

  • Symmetric design

  • Fit installation - filling not visible

  • One sided duct connection ended with Grille


Air Transfer Grille

The F-B90 multi-blade fire damper can be used as an air transfer grille with cold smoke tightness.


Symmetric Structure

The unit has a symmetric structure and mechanism that allows for access from both sides.


Heat or Smoke Activation

In case of fire, when the air temperature in the duct exceeds 72 °C or 74 °C, the thermal fuse melts activating damper blade closure. In addition a standalone smoke detection available with selected activation types.


The F-B90 multi-blade fire damper provides efficient passive fire protection in a range of installations. It’s designed to utilize compartmentalization to prevent the spread of smoke, fire and toxic gases. In the event of a fire, when the air in the duct exceeds 72 °C or 74 °C, the thermal fuse will melt in both the actuator and manual versions. This automatically activates the closure of the damper blade. The damper blade is then mechanically locked in the closed position. An optional smoke detector is also available for selected activation types.

Available in different sizes, F-B90 fire dampers are CE certified following the Construction Products Regulation according to EN 15650:2010. Dampers are tested according to EN 1366-2:2015 and classified according to EN 13501-3 + A1:2009. The fire damper, together with its installation, form an inseparable part of the fire resistivity rating. The casing of the F-B90 is made of galvanized sheet metal. The damper casing and two covers protect the mechanism and the actuator.