Ductwork runs through a building, and wherever it passes through a fire-rated wall or floor it creates a potential hole in that fire barrier. Fire and smoke dampers are what close that hole in a fire. They are one of the least glamorous parts of a ventilation system and one of the most safety-critical — and they are frequently the part nobody has tested in years.
What they do
A fire damper is a mechanical barrier inside the ductwork that closes when it senses fire, stopping flames and heat spreading through the ventilation system from one fire compartment to another. A smoke damper does the equivalent for smoke, which kills more people in fires than flames do. Many modern dampers are combined fire and smoke dampers, triggered by the building’s fire alarm system as well as by heat.
The building is divided into fire compartments precisely to contain a fire and buy time to evacuate. Ductwork that punches through those compartments would defeat the whole strategy — unless every penetration has a working damper.
Why testing is non-negotiable
A fire damper that has seized, corroded or been painted over will not close when it is needed, and there is no way to know that without testing it. This is why the standards require regular drop testing: physically triggering each damper to confirm it closes fully and reseats correctly. For most buildings that means annual testing, with newly installed dampers tested a year after commissioning.
Under the Regulatory Reform (Fire Safety) Order, the responsible person must ensure fire safety measures are maintained in working order — and fire dampers are squarely within that duty. A fire risk assessment that cannot show dampers have been tested is a gap, and it is one insurers and enforcing authorities take seriously.
The common failures
We routinely find dampers that have never been tested since installation, dampers with no access panel so they cannot be tested without cutting into the duct, and dampers seized solid by corrosion or years of grime. Access is the recurring theme — a damper you cannot reach is a damper you cannot maintain, and designing in proper access panels is half the battle.
Keeping them compliant
A compliant regime means: identifying and locating every fire and smoke damper in the building, ensuring each has safe access for testing, drop-testing them at the required frequency, repairing or replacing any that fail, and documenting the lot. That documented test record is what satisfies your fire risk assessment.
We test, repair and replace fire and smoke dampers as part of ventilation system maintenance, and we sort out access where dampers have been installed without it. If you cannot put your hand on a recent damper test record, that is a fire safety gap worth closing now.
