fire damper

Guide for Facility Managers on the Testing and Maintenance of Fire Dampers

fire damperA fire damper can be defined as “a device installed in ducts and air transfer opening of an air distribution or smoke control system designed to close automatically upon detection of heat. It also serves to interrupt migratory airflow, resist the passage of flame, and maintain the integrity of the fire rated separation.” Its primary function is to prevent the passage of flame from one side of a fire-rated separation to the other.

The significant protection capabilities of fire dampers to life and property are now widely recognized by Facility Managers throughout the United States. More and more Authorities Having Jurisdiction (AHJ’s) and building owners are requiring fire dampers to be operational tested and maintained on a regular basis.

AHJ’s are requiring operational tests to determine if the damper will function when needed in order to resist the spread of fire. Operational testing normally involves removing or melting the fusible link and letting the damper close. Once the damper has proven to close, it is reopened and the fuse link replaced. All the dampers installed in a building must be tested prior to occupancy and again 1 year later under normal operating conditions. Reference NFPA 80 and NFPA 105 for more information.

Applicable Standards

NFPA 80 is the National Fire Protection Association standard that regulates the installation and maintenance of assemblies and devices used to protect openings in walls, floors and ceilings against the spread of fire and smoke within, into, or out of buildings.

NFPA 105 is the standard which prescribes the minimum requirements for smoke door assemblies and smoke dampers that are used as a means to restrict the flow of smoke though openings to provide safety to life and protection of property.

Fire Dampers must meet the UL555 Test Standard. UL (Underwriters Laboratories) states that the requirements of UL555 cover fire dampers that are intended for use where air ducts penetrate or terminate at openings in walls or partitions; in air transfer openings in partitions; and where air ducts extend through floors as specified in the standard for installation of air-conditioning and ventilating systems, NFPA 90A.

Testing and Maintenance

AMCA presents a valuable guide for commissioning and periodic performance testing of fire, smoke and other life safety related dampers. This guide provides recommendations for the proper commissioning of fire and life safety related dampers and details the appropriate intervals and methods for performing periodic performance testing of these dampers. This guide can be downloaded for free from AMCA’s website below.

AMCA Guide for Commissioning and Periodic Performance Testing of Fire, Smoke and Other Life Safety Related Dampers

To the facility manager operational tests and regular maintenance can present a couple of challenges:

  1. Most fire dampers are installed in areas of the building that are not easily accessible. Fire dampers are installed in penetrations of fire rated walls and floors as required by the building code and access to the damper itself is normally through an improperly sized access door.
  2. Fire dampers can be extremely difficult to test and reset due to their design (all manufacturers’ utilize the same basic curtain type design). There are two main types of fire dampers: dynamic fire dampers and static fire dampers. Dynamic fire dampers have been UL tested and proven to close against system air pressure and velocity. Static fire dampers, on the other hand, are UL tested but have not been proven to close against system air pressure and dynamic fire dampervelocity. The main difference between the two designs is dynamic dampers (in most cases) utilize springs to pull the curtain closed against the air pressure and velocity while static dampers rely solely upon gravity to pull the curtain closed (static dampers designed for floor installation utilize closure springs). The spring shape and size determine the air pressure and velocity against which the dynamic fire damper closes.

Dynamic fire dampers are becoming more popular with designers as dynamic dampers may be used in either a static system (fans off) or dynamic system (fans on) while static dampers can only be used with static systems.

Limited access and closure springs do not make dynamic fire dampers testing and maintenance friendly despite being life and property friendly as they are guaranteed to close if properly applied and installed.

A solution to the operational acceptance testing problems is to know the testing requirements beforehand. Coordinate with the AHJ and determine what they will accept for testing procedures.

Since dynamic dampers are proven to close, the solution may be a simple installation inspection to make sure the dampers are installed properly with no obstructions.

A solution to the maintenance testing is not so simple. Maintenance should be performed per NFPA80 and NFPA 105 requirements: “Each damper shall be tested and inspected after the damper is installed, then one year after installation. The maintenance testing and inspection frequency shall then be every 4 years, except in hospitals, where the frequency shall be every 6 years.”

Motorized fire damperMore often than not, the building will be occupied and access to the damper remains a problem; however the use of a motorized fire damper that can be operated from a remote, easily accessible location and can be equipped with position indication for operation verification. A motorized fire damper can be more easily maintained compared to a standard dynamic fire damper and contributes to maintenance and insurance savings. All motorized fire dampers are dynamic rated and may be utilized in place of any static or dynamic curtain blade fire damper.

Dynamic, multiple blade fire dampers provide another solution to the access and maintenance issues posed by the dynamic curtain blade dampers. Multiple blade fire dampers are easy to both test and reset since the blades can be operated and held open via a hand lever or a pair of pliers while the fuse link is replaced. An additional solution for round ducts is the use of a true round fire damper. Round fire damper allows the fusible link to be replaced easily then the damper can be adjusted to its full-open position.

Summary

Testing and maintenance of fire dampers, especially dynamic, curtain fire dampers, can be extremely difficult. There are, however, alternative types of dynamic fire dampers that make testing and maintenance easier. The cost of these other dampers is typically greater than standard dynamic fire dampers but savings can be easily realized in other areas like maintenance and insurance. Before designing around “standard” curtain type dynamic fire dampers, check with the Authorities Having Jurisdiction (AHJ’s) and the building owner to determine the testing and typical multi-blade dynamic fire damper maintenance requirements.

Ruskin Wireless InspectorRuskin Damper Testing Solutions

Ruskin can present a solution to your testing problems, our patented Wireless Damper Inspector system. Utilizing radio frequency, this remote control system cycles actuators of all life safety motorized dampers especially those that are installed in hard to reach or even inaccessible locations. Ruskin Wireless Damper Inspector satisfies NFPA requirements* for both initial and periodic testing of life safety dampers.

Ruskin Classic InspectorRuskin’s Classic Inspector™ consists of a Panel PC, UPS and pre-loaded software. The Panel PC communicates with damper interfaces to provide intelligent monitoring of motorized dampers and manual fire dampers. The data network cabling represents a substantial cost reduction when compared with conventional systems.

For more information about Ruskin’s complete product line, application and design support, and our state-of-the-art manufacturing capabilities, contact your local Ruskin representative nearest you or Contact Ruskin directly at (816) 761-7476.

Useful References

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Fire smoke Damper Required in Commercial Buildings

What is the purpose of a fire damper?
Fire Dampers are used to maintain the required ratings of fire rated barriers (walls, partitions, floors) when they are penetrated by ductwork.
How does a fire damper work?
When a rise in temperature occurs a fire damper will close and prevent the spread of flame through the barrier. Dampers are typically curtain style that will close (shut) when a fusible link melts. The fusible link typically melts when the temperature rises to 165 degrees Fahrenheit. In some circumstances higher degree fusible links (e.g. 212°F) are installed in ductwork with consistently higher normal temperatures, such as hot decks in dual duct systems. Fire dampers are certified by Underwriters Laboratories (UL) to carry hourly fire resistance ratings, typically 1.5 to 3 hours.
What types of fire dampers exists?
Dynamic Fire Dampers – Dynamic Fire Damper is a damper that is approved for use where the HVAC System blower will remain on during an alarm (or “Fans On”). Dynamic fire dampers are rated to close against moving air.
Static Fire Dampers – Static Fire Damper is a damper that is approved for use where the HVAC System blower will cycle off during an alarm (or “Fans Off”).
What is the purpose of a smoke damper?
Smoke dampers are used is ductwork and air transfer openings that are designed to resist the passage of air and smoke. Smoke dampers may be required in smoke barriers and other smoke controlled systems.
How does a smoke damper work?
Typically smoke dampers are operated by smoke detectors in the ductwork that will close the smoke damper when smoke is detected. Smoke detectors often are hard wired to a central alarm panel in which the alarm will relay a signal to the smoke damper to cause smoke damper closure. The closure of smoke dampers are done by an actuator – the actuator is either electric or pneumatic. The actuator utilizes the jackshaft and linkage to open and close the blades of the smoke damper. Smoke dampers are UL certified with an air leakage class rating.
What is a Combination Fire and Smoke Damper?
These dampers are used in areas where both smoke and fire barriers are located to prevent the passage of both smoke and flames.
What is a Corridor Damper?
Corridors are means of egress travel to an exit. Corridor dampers are fire and smoke dampers that have been designed for use in corridors.
What is a Ceiling Damper?
Ceiling dampers lessen the passage of heat in fire resistance ceilings where ducts are made only through ceilings.
What is a fire barrier?
Fire barriers are fire-resistant rated horizontal or vertical assemblies designed to stop the spread of fire.
What is a smoke barrier?
Either vertical or horizontal, the smoke barrier is a continuous surface such as a wall, floor, or ceiling constructed to restrict the movement of smoke.
Fire Doors
What is a Fire Door?
A fire door, like a fire damper, is a method of passive fire protection used to prevent the spread of fire and smoke between fire barriers.
What are the main purposes of a fire door?
Serve as a regular door;
Provide ready egress during a fire;
Keep fire from spreading throughout a building;
Protect life and property
What determines a fire doors rating?
The fire rating of the wall that the door is installed determines the fire rating of the door.
What are typical wall rating / door rating usages?
Wall Rating Door Rating Description and Use
4 Hour 3 Hour These opening are in walls that separate building or divide a single building into designated fie areas.
2 Hour 1-1/2 Hour Openings of this type are used in enclosures of vertical communication or egress through buildings. Examples of these types include stairwells and elevator shafts
1 Hour 1 Hour These door assemblies divide occupancies in a building.
1 Hour 1/4 Hour For use where there are openings in corridors or room partitions.
2 Hour 1-1/2 Hour This openings is in a wall where there is the potential for severe fie exposure from the exterior of the building.
1 Hour 1/4 Hour This opening is in an exterior wall that has the potential to be exposed to moderate to light fire from the exterior of the building.
1 Hour 1/3 Hour These openings are in corridors where smoke and draft control is required. The minimum opening is 1 Hour.
When are fire doors needed?
Where a door leads to exit stairwells and horizontal exits.
Where a door leads to a hazardous area.
Where a door has an Exit sign around it.
Generally, where a door leads to a hallway or from one fully enclosed room to another.