Periodic testing of life safety systems and dampers is required by the codes. While there is some state or local variation, the requirements are shown in Chart 1. While the focus of this article is the dampers, the entire smoke control system is required to be tested according to the schedule labeled “Smoke Control Systems & Dampers.” A clear distinction must be made among the damper applications in order to determine the schedule that conforms to codes. The second part of this article explains the differences among the dampers and applications.
Chart 1: Periodic testing requirement for dampers.
Codes and Referenced Standards
Chart 1 originates with two primary codes – the International Building Code (IBC)1 and the International Fire Code (IFC).2 It is the IFC that defines or references most testing requirements. It references NFPA 803 (fire) and NFPA 105 4 (smoke) directly for the containment damper requirements. These two standards have details on what to test or inspect, periodic requirements, and replacement information. The IFC does give the smoke control system requirements directly – 909.20.4 for dedicated systems and 909.20.5 for non-dedicated systems. NFPA 90A5 , NFPA 92A6 and NFPA 92B77 are frequently referred to with respect to testing. However, they are not referenced by the IBC or IFC and only with respect to smoke protected seating by NFPA 101, the Life Safety Code.8
How often does the National Fire Protection Code 80 and 105 require testing?Both standards state the requirement for testing is one year after installation and then every 4 years (hospitals every 6 years). Chapter 6 Installation Testing, and Maintenance of Smoke Damper is the most important chapter with respect to testing smoke and combination dampers. |
Dampers Required by Chapter 7 of the International Building Code (IBC)
Chapter 7 of the IBC regulates fire resistive rated construction. Fire dampers are installed in firewalls, fire barriers, fire partitions, and horizontal assemblies. Smoke dampers are installed in smoke barriers, and smoke partitions. Combination fire and smoke dampers that are required by Chapter 7 can be installed in any of the applications that require both fire-rated construction and smoke containment. They are meant to resist the passage of flames and smoke particulates.
Most fire dampers have fusible links that melt at (typically) 165°F (74°C) allowing gravity or a shaft spring to close the damper. Fire dampers are rarely actuated in the Americas (although they are regularly actuated in Europe so that they can be automatically tested). See Figure 2 for a typical curtain fire damper. There are several types and ceiling dampers are similar.
Figure 2 Curtain fire damper (photo courtesy of Greenheck Fan Corporation).
A smoke damper is connected to a duct smoke detector or to a relay from the fire alarm or smoke control panel. In event of a fire and concomitant smoke, an actuator springs closed to close the damper and prevent smoke movement from one area to another. All smoke dampers are actuated since there is no method to physically sense smoke and electrical control is required.
A combination fire and smoke damper looks very similar to a smoke damper but has a high-temperature sensor to close the damper from the heat along with the local smoke detector.
Figure 3: Combination fire and smoke damper (drawing courtesy of Ruskin Company).
Combination fire and smoke dampers can be controlled several ways. Most commonly on modern dampers is use of an electrical temperature activated sensor-switch. When the contacts are closed, the actuator is powered and drives the damper open. When fire/heat is detected, the contacts open and the damper shuts. See Figures 3 and 4. In addition, a smoke detector or relay contact from the area smoke detection system panel is wired in series with the temperature switch. If smoke is detected, the contact opens and the actuator springs the damper closed. See Figure 3. The smoke detector is installed within 5 ft. of the damper or an area smoke detection system may control the damper’s closing. The wiring for the typical combination damper is shown in Figure 4.
Though not required by Chapter 7, in order to automatically test these dampers, position indication switches may be installed. They can power locally exposed monitoring lights or, typically via a network, indicate position to a testing panel. These dampers are best referred to as containment or compartmentation dampers as that is their function; this clearly distinguishes them from smoke control dampers discussed below. They are often referred to as “passive” protection although they are active in as much as they move to close holes in fire or smoke walls, barriers, and partitions.
Figure 3: Containment fire & smoke damper with smoke detector.
Figure 4: Controls and wiring for a combination fire & smoke damper.
Dampers required by Chapter 9 of the International Building Code (IBC)
IBC Chapter 9, Fire Protection Systems, regulates installation of engineered smoke control systems (as well as alarms and sprinklers). In order to remove smoke or prevent the movement of smoke into protected spaces, dampers, fans, architectural reservoirs, and smoke chimneys may be employed. These are considered active systems.
Some of the occupancies where smoke control systems are required are in atria, stairwells, underground buildings, and large spaces like malls and auditoriums. Some local codes also require additional protection in corridors and any exit passages.
The dampers employed for smoke control are generally of the same physical construction as those for containment. Some smoke dampers are aluminum whereas fire & smoke dampers are galvanized or stainless steel.
It is the control capability of the smoke control system damper that is different. The system is more sophisticated and requires coordination among alarms, sprinklers, fans, doors, and dampers. The containment damper is closed by only a local duct smoke detector) or in the case of the combination fire & smoke damper, by the detector or a single high temperature sensor. The detector can be mounted at the factory or field installed. UL555S requires that both the sensor and actuator be factory installed initially.
In particular, smoke control dampers are connected to the fire fighters’ smoke control system panel for manual override control and position indication and verification. These dampers are often referred to as “re-openable” since they can be manually opened or closed although they are normally in automatic mode. See Figure 5 for an example damper. Figure 6 shows the full wiring for override and position indication. Note that modern systems typically use a network for the long wire runs. For this example, discrete wiring is shown.
Figure 5: Smoke control system damper with sensors (photo courtesy of Pottorff).
Figure 6: Auto-Off-Manual switch and re-open able damper with sensors and actuator.
In addition to distinguishing between Chapter 7 and Chapter 9 dampers, there are two types of smoke control system dampers – dedicated and non-dedicated. A dedicated system is used for no other purpose than smoke control. For example, an atrium make-up air damper and atrium smoke exhaust fan damper are not used in day to day operation. A non-dedicated system is used for normal HVAC or ventilation and is operated on a regular basis. If it fails, a service call would be generated and it would require immediate repair. Failure of dedicated system dampers will not be evident without operation so they must be tested more frequently to ensure safety.
Testing procedures
Other than stating that both initial and periodic inspection and testing of dampers are required, the codes do not detail how or precisely what steps are to be taken. However, the intent is clear – compliance with NFPA 80 and NFPA 105 along with damper manufacturer instructions are expected.
It is beyond the scope of this article to detail the standards; however, a brief description is provided below.
In NFPA 80, section 19.3 Operational Test, fire damper testing is detailed. The essential test is that the damper will open and close and no obstructions are present. NFPA 729 is referenced when any smoke detection is present. The operation must be under the airflow conditions that the system will encounter. Fusible links must comply with NFPA 90A and UL33.10 Documentation must be maintained and any deficiencies reported and corrective action noted. It also states that “repairs shall begin without delay” and following repair shall be operational tested again.
Both standards state the requirement for testing one year after installation and then every 4 years (hospitals 6 years).
NFPA 105 is worded very similarly to NFPA 80 and contains many of the same requirements. Chapter 6 Installation, Testing, and Maintenance of Smoke Dampers is the most important chapter with respect to testing smoke and combination dampers. An operational test is required upon installation and all indicating devices must work correctly. NFPA 92A is referenced for periodic inspection and testing. Repairs must “begin as soon as possible” and all maintenance must be documented.
One provision that bears examination is found in section 6.5.5: “The damper shall be actuated and cycled as part of the associated smoke detector testing in accordance with NFPA72, National Fire Alarm Code.” Smoke detectors must be tested yearly and when they are released, the actuator of the smoke or combination fire and smoke damper will spring closed (or for smoke dampers that must open, spring open). The sound of the actuator and the time it takes are tantamount to a test. Thus a sample inspection for blockage – very rare after construction is completed – could reduce cost of testing.
The Air Movement and Control Association (AMCA)11 have published a document with input from all the damper manufacturers titled Guide for Commissioning and Periodic Performance Testing of Fire, Smoke and Other Life Safety Related Dampers. It contains some of the material found in NFPA 80 and NFPA 105 along with other details. AMCA does not require the need for visual inspection of motorized dampers with end switches that communicate to a panel or lights.
Belimo Americas has also published a cross reference and instructions for replacement actuators on dampers.12 Included is a form to leave on site for the fire marshal or building official which complies with the documentation requirement of NFPA 80 and NFPA 105. These instructions focus on the old obsolete actuators from the 1980s to date. Often the dampers are in perfect condition and only one or more of the electrical components are defective.
Summary
The first step in establishing a periodic testing schedule for dampers is to identify whether they are employed for Chapter 7 or Chapter 9 code requirements. Once that is achieved, operational testing itself is straightforward. To what extent manual inspection is required for smoke control dampers is up to the local inspector. Since smoke control dampers have blade switches or their actuators have auxiliary switches, a test of the entire smoke control system will test the dampers and position indication is automatically shown on the fire fighters’ smoke control panel.
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1International Building Code, 2012, International Code Council, Inc., Country Club Hills, IL 60478-5795.
2International Fire Code 2012, ibid.
3NFPA 80 Standard for Fire Doors and Other Opening Protectives , National Fire Protection Association, NFPA, 1 Batterymarch Park, Quincy, MA 02169-7471.
4NFPA 105 Standard for the Installation of Smoke Door Assemblies and Other Opening Protectives, ibid.
5NFPA 90A Stadard for the Instalation of Air-Conditioning and Ventilating Systems, op.cit.
6NFPA 92A Standard for Smoke-Control Systems Utilizing Barriers and Pressure Differences, op.cit.
7NFPA 92B Standard for Smoke Management Systems in Malls, Atria, and Large Spaces, op.cit.
8NFPA 101 Life Safety Code, National Fire Protection Association, op.cit.
9NFPA 72, National Fire Alarm Code, op.cit.
10UL 33, Standard for Heat Responsive Links for Fire-Protection Services, Underwriters Laboratories Inc. (UL), 333 Pfingsten Road, Northbrook, IL 60062-2096.
11 Air Movement and Control Association International, Inc. 30 West University Drive, Arlington Heights, IL 60004-1893 U.S.A.
12http://www.belimo.us/cms/sh/firesmoke/index.php BELIMO Automation AG.