Retrofit of Fire Dampers with low pressure Extinguishing Technology
As an automatic shut-off, fire dampers prevent fire and smoke from spreading through the ventilation duct bilaterally connected to the flap. Fire dampers in existing buildings that were built before 1988 must be adapted to the current requirements. A low-cost renovation measure is often sufficient for this.
Renovation of Fire Dampers
as an inexpensive Alternative
If construction occurs, the building authority requires the modification of the building or its fixtures. This requires a connection between the old structure and the modification. Dependence between the old and new part of the building is sufficient. As a result, both the new parts of buildings and the old structure meet the current requirements.
In many cases it helps to renovate the fire dampers by installing a low-pressure extinguisher system. Major structural changes and high follow-up costs can be avoided, without compromising on safety.
Fire dampers are part of the ventilation systems in buildings. As an automatic shut-off, they prevent fire and smoke from spreading through the ventilation duct bilaterally connected to the flap. Fire dampers are installed into walls and ceilings for reasons of fire safety between sections of buildings to secure each fire area, and they are therefore generally within or directly connected to the associated fire wall. In normal operation, the fire damper is opened to allow air passage. But the ventilation duct stops and closes in case of fire.
The need for renovation may result from the following reasons:
Inadequate Fire Resistance
Insufficient Smoke Seal
The Presence of Components containing Asbestos
Retrofit of Fire Dampers – the Concept
Low pressure extinguishing technology can be used as an alternative measure for fire dampers, which are currently used in the old building and do not meet the currently valid DIN regulations or the building regulations.
Such fine spray extinguishing systems are sprinkler systems that spray fire water drops with the low pressure of up to 10 bar at predetermined specifications in order to achieve a better extinguishing effect. Compared with conventional sprinkler technology they need a smaller pipe diameter and smaller component sizes which can be installed easily into existing ventilation shafts. They are efficient, cost-effective and at the same time ensure the appropriate fire resistance increase to the existing fire zone without increasing the necessary effort for structural fire protection measures.
Retrofit of Fire Dampers – the Funcionality
The extinguishing nozzles that produce a water mist in case of fire are installed in the channel in the ventilation duct in the area of the fire dampers. The water mist causes a cooling of the channel on the one hand and on the other an absorption or leaching of the flue gases. This creates a bond and a reduction in toxic and corrosive fire decomposition products.
The low-pressure extinguisher system can be operated from different water supplies. It is possible to supply water via a sprinkler system or internal fire hydrants.
Another option is connection to a sufficiently large mains water supply. The required system pressure of between 3 and 10 bar is provided via a downstream pressure pump. The extinguishing water is passed within a few seconds as required to the extinguishing nozzles via a tube system made ??of stainless steel.
Fire detection is provided by a ventilation duct smoke detector and heat detectors. The complete test is available from a central location via a peripheral test as an additional module.
ADVANTAGES OF A RENOVATED FIRE DAMPER
Immediate cooling of the Ventilation Duct
or the Fire Damper
Effective Washing and System Cooling
Considerable Reduction of the Spread of harmful Gases
Optional Testing Facility
Renovation possibilities for older type Fire Dampers
manufactured before 1974
- Fire dampers are installed in type A (only with stop pin) or type B (only with stop angles) or type C (with rotating end brackets). The leakage with these flaps is relatively large, so that a sufficient smoke seal is often not in place. Sealing elements have only needed to be used since 1974 in order to meet the permissible leakage.
manufactured from 1974 to 1988
- Following the introduction of the test mark obligation for fire dampers in 1974 because there were no suitable alternative materials, several fire damper components containing asbestos were used up to 1988.
made until the end of 1980
- They contain asbestos building materials in flap leaves, frames, canopy panelling. Calcium silicate plates were used with the commercial name Marinite 36. They contained the asbestos chrysotile and amosite.
- They contain materials using asbestos in gaskets in the stops, sometimes even in externally accessible covers of the installation area. Asbestos foam plastic with the trade name Litaflex KG25 was used. It includes asbestos chrysotile.
from end of 1980 up to 33rd calender week of 1988
- This included the seals of the damper blade stops and possibly covers with the asbestos-containing material Litaflex KG25.
Any questions to your own fire protection project?
Our experts are happy to help you further.
ALMOST THREE DECADES IN IMPLEMENTING FIRE PROTECTION SYSTEMS
AND STILL ON FIRE FOR IT.