Fire Dampers & Fire Smoke Dampers

Shop UL-classified fire dampers, smoke dampers, and combination fire and smoke dampers from Aire Technologies for ducts that pass through fire-rated walls, floors, and shafts. Choose static fire dampers for systems that shut down fans in a fire, dynamic fire dampers for systems that keep running, and Type C models with round collars that connect directly to spiral ducts. Smoke-rated options include Class I and Class II combination fire smoke dampers, a Class I smoke damper, and a Class I corridor damper. Send us your schedule and we’ll match every damper on the job.

Shop by type: Static Fire Dampers | Dynamic Fire Dampers

How a fire damper works

A fire damper is a steel curtain held open inside a frame by a fusible link. When duct air reaches the link’s rated temperature (165°F is standard), the link melts and the curtain closes, blocking flame from traveling through the ductwork into the next fire compartment. Fire dampers are tested to UL 555 and rated 1-1/2 hours or 3 hours to match the wall or floor they sit in.

Frequently asked questions

What is a fire damper in HVAC?

A fire damper is a device installed in ductwork where it passes through a fire-rated wall, floor, or shaft. A fusible link holds a steel curtain open; when heat melts the link, the curtain closes and blocks fire from spreading through the duct. Building codes require them at most rated penetrations. 

What’s the difference between a fire damper and a fire smoke damper?

A fire damper responds to heat only, closing when its fusible link melts. A combination fire smoke damper also closes on a signal from a smoke detector or fire alarm, through an electric actuator. Fire dampers are tested to UL 555; fire and smoke dampers carry both UL 555 and UL 555S listings.

What’s the difference between static and dynamic fire dampers?

A static fire damper is rated to close only when there’s no airflow, so it’s used in systems that shut fans down on alarm. A dynamic fire damper is rated to close against moving air at a tested velocity and pressure, for systems where fans keep running during a fire. 

What do Class I and Class II mean on a smoke damper?

They’re leakage ratings under UL 555S. A Class I damper leaks no more than 4 CFM per square foot at 1 in. w.g. of pressure; Class II allows up to 10. Class I is the tighter seal and the common requirement in smoke control systems.

What temperature does a fire damper close at?

Standard fusible links melt at 165°F. Higher-rated links (212°F and 286°F are common) are used in systems that normally run hot or in smoke control systems where the damper needs to stay open longer.

How often do fire dampers need to be inspected?

NFPA 80 and NFPA 105 call for testing 1 year after installation, then every 4 years. Hospitals follow a 6-year cycle. Each test confirms the damper closes fully and the link or actuator works, and the damper is reset afterward.

Does a fire damper need an access door?

Yes. Building and mechanical codes require an access door in the duct next to every fire damper, sized so an inspector can reach the link and reset the curtain. 

How long does shipping take for fire and smoke dampers?

In-stock, ready-to-ship fire dampers arrive within 2 to 5 days after they ship, depending on your location and shipping method. Dampers built to your duct size or rating have their own production time, listed on the product page and in your order confirmation. Larger dampers may ship by pallet and arrive separately from smaller items in the same order. If your inspection or close-out date is fixed, contact us before ordering to ask about expedited production or delivery.