How The Outer Wall’S Fire Damper Is To Be Used?

Fire dampers are triggered by a fusible link or thermal sensor that melts at a specific temperature, usually around 165°F or 74°C. When this link melts, the damper’s blades close, sealing off the duct and preventing the fire from spreading to other parts of the building. They are installed in the plane of a wall or floor opening, except for those designed to specifically mount outside the plane.

Fire dampers are designed to maintain compartmentation and prevent the spread of fire through ventilation ductwork. They are designed to allow air to flow through in normal operation. A standard 1.5-hour or 3-hour fire or combination fire/smoke damper must be installed with the centerline of the blades in the closed position within the plane of a wall or floor. Some manufacturers, like NFPA, offer multi-blade dampers that operate similarly to curtain type dampers.

Fire dampers are required in locations where ducts pass through fire-resistant walls, floors, and ceilings that define a compartment. They can be actuated, opened, and closed in less than 60 seconds, either by external control signals or through a smoke control system. Smoke dampers are integrated into most mechanical 909 smoke systems and cannot interfere with passive fan shutdown. Ducts and air transfer openings of fire barriers should be protected with listed fire dampers installed in accordance with their listing.

Fire dampers can be installed in the floor (horizontal) with vertical airflow or in walls (vertical) with horizontal airflow. Fire dampers installed in assemblies having a fire-resistance rating of 3 hours or greater must have an hourly fire-protection rating of 3 hours.

What is required for a 2 hour fire rated wall?

A 2-hour fire-rated wall is a type of wall that can prevent fire spread for at least two hours. It requires rigorous testing of the wall panel or materials to demonstrate fire resistance and structural integrity. A 2-hour fire-rated wall must have a minimum thickness of 5 inches. Other types of fire-rated walls include 1-hour and 3-hour ratings, with 1-hour walls offering less protection and 3-hour walls maintaining structural integrity for longer. 1-hour walls are 4 inches thick, while 3-hour walls must be 6 inches thick. Both types are popular in construction and building design.

Are fire dampers required on external walls?

Fire dampers are essential for protecting ductwork that passes through fire-resistant walls, floors, and ceilings in compartments. They are also necessary for non-ducted air transfer openings and penetrations in floors or shaft enclosures. Exhaust ducts are generally required, but may not be necessary if used for venting toxic gases. Consult a passive fire protection specialist if uncertain.

Installing fire dampers requires careful observance of manufacturers’ instructions and avoiding pitfalls like installing them upside-down or at 90 degrees to their proper position. Incorrectly oriented dampers cannot function when they rely on gravity to close, resulting in no protection. Consult a passive fire protection specialist for guidance.

How do fire dampers operate?

Fire dampers prevent flames from crossing a fire barrier and are installed near walls or floors. They respond to heat and shut when the temperature reaches a set point. Smoke dampers detect smoke and automatically close or can be activated remotely. They resist the passage of smoke, toxic gases, and air through a fire barrier. Inhalation of smoke and toxic gases is the largest cause of death in a fire, making it essential to contain them for at least as long as possible for evacuation.

Should fire dampers be open or closed?

The damper in a fireplace should be kept closed when there is no fire or coals burning to prevent warm air from being lost up the chimney. Open the damper before starting a fire and keep it open until all embers and coals have burned out. If the damper is damaged or missing, close it tight to contain the heat within the house.

To address an older fireplace with a missing or damaged damper, a “lock-top sealing damper” is recommended. This device replaces the cap on the top of the chimney with a spring-loaded damper, effectively sealing the chimney at its top. These dampers come in different sizes and shapes but function the same as other dampers, sealing up the fireplace and preventing cold outside air from coming down the chimney or losing warm, heated air from the house up the chimney.

What makes a 1-hour fire wall?

The UL U493, UL Design U348, and PER UL U305 are fire-rated wall assemblies used in interior, non-load bearing walls. The U493 uses steel studs 16″ o. c., two layers of SCX gypsum, ecobatt insulation, an air space, more studs, insulation, and a final layer of gypsum for a 1-hour fire-rating. This type of wall assembly also helps with energy efficiency due to staggered studs and air gap. The U348 is ideal for load-bearing exterior walls, requiring a 1-hour fire-rating from the interior side only. The PER UL U305 is a wood stud, load-bearing design used as a chase wall, consisting of one layer of SCX gypsum, 2×4 wood studs, a 1″ air gap, and a final layer of SCX gypsum.

Are fire dampers required in a 2 hour wall?

Fire dampers are necessary for air ducts that penetrate walls rated for 2-hours or more, all air transfer openings in rated walls, and some penetrations of rated floor assemblies and shaft enclosures. Smoke dampers are required at penetrations of smoke barriers, unless the HVAC system is fully ducted and a sprinkler system is installed. Smoke dampers are also required in air transfer openings in smoke partitions. Combination units that are both smoke and heat responsive may be used for penetrations requiring both types of dampers.

Are fire dampers required in 30 minute walls?

The majority of walls should be capable of providing a fire resistance rating of at least 30 minutes, with a standard stud wall typically offering a rating of 12. The application of 5mm plasterboard on either side provides a fire resistance rating of 30 minutes. The use of fire-resistant plasterboard results in an enhanced rating of 60 minutes.

Should the damper be open or closed for a fire?

A chimney damper is a safety feature that prevents conditioned air from escaping through the flue when not in use. It should be opened when starting a fire to allow proper airflow and allow smoke to escape. A closed damper can restrict airflow and pose a safety risk. There are two main types of chimney dampers: throat dampers and ash dampers. The throat damper, built into the fireplace and visible at the top of the firebox, closes the base of the chimney and insulates the home from cold air.

Where should a damper be installed?

Fire dampers are installed in a variety of locations within a building, including ducts, air outlet openings, shaft walls, fire barriers, and other fire resistance-rated assemblies. The installation of these devices is typically required by a building or life safety code, such as those governing occupancy separation walls, horizontal exit walls, corridor walls, and floor-ceiling assemblies.

How should fire dampers be installed?

Fire dampers are crucial for indoor ventilation and fire safety, installed upstream and downstream of air handling units, including supply and return ducts. They prevent the spread of fire or smoke through the HVAC system, which can circulate hazards to other parts of the building. However, the installation, testing, and maintenance of fire and smoke dampers are often overlooked in building and facilities management. These fail safes are shutters installed in ductwork that can be closed manually or automatically when fire or smoke is detected by sensors.

They are subject to building regulations and standards in the UK, typically set out in documents such as the Building Regulations and guidance documents published by organizations like the British Standards Institution (BSI), the Building Research Establishment (BRE), and the Building and Engineering Services Association (BESA).