CFC · California Fire Code

When are fire dampers or smoke/air‑control dampers required at penetrations?

If a supply, return or exhaust duct is allowed through a fire wall, fire barrier, shaft, corridor or smoke barrier, the California code generally requires a listed fire damper or smoke damper at that penetration (with specific exceptions for tested assemblies, certain continuous duct systems, or engineered smoke control). Check **§ 717.5.1** and **§ 717.5.2** for the locations and **Table 717.3.2.1** for minimum damper ratings; coordinate with the Mechanical Code and the smoke control analysis when exceptions are claimed.

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Last reviewed: July 6, 2026

What the code requires — plain English

The California code requires that when ducts or air‑transfer openings penetrate certain fire‑resistance assemblies you must protect those penetrations with listed fire dampers, smoke dampers or combination fire/smoke dampers as specified in the duct/penetration rules. The controlling provisions are § 717.5.1 (fire walls) and § 717.5.2 (fire barriers); both set the locations where dampers are required and list the exceptions and special conditions. See § 717.5.1 and § 717.5.2 for the base requirements and exceptions.

The single most important rule: if a duct or air‑transfer opening is allowed through a required fire wall or fire barrier, the opening must be protected with the listed damper type the code calls for unless one of the code exceptions applies.

Requirements in detail

1) Fire walls — when a fire damper is required

  • If a duct or air‑transfer opening is permitted through a fire wall, it must be protected with a listed fire damper, installed per its listing. This is the requirement in § 717.5.1 and it specifically ties the permitted penetrations to Section 706.11 (fire wall provisions). § 717.5.1.
    • Note: § 706 is referenced (see § 706.11) in connection with which penetrations are permitted in fire walls; the provided files reference 706.11, but the full text of § 706 was not retrieved here.

2) Fire barriers — when a fire damper is required

  • In occupancies other than Group A, E, H, I, L and R and in most ordinary buildings, ducts and air‑transfer openings of fire barriers must be protected with listed fire dampers installed per their listing (this is § 717.5.2).
  • The code also prohibits ducts/air openings from penetrating interior exit stair/ramp enclosures or exit passageways except as specifically allowed. § 717.5.2.

3) Smoke dampers and other locations (overview)

  • Where smoke control of an enclosure is required (smoke barriers, smoke partitions, corridors that require smoke & draft doors, fire walls serving as horizontal exits, etc.), the code requires listed smoke dampers (or combination devices) at duct or air‑transfer openings — see multiple subsections of § 717 (examples: § 717.5.1.1, § 717.5.2.1, § 717.5.5) for smoke damper requirements.

4) Damper ratings (how long they must withstand fire)

  • Use the damper minimum fire‑ratings called out by the code (Table 717.3.2.1): 1.5 hours minimum for penetrations of assemblies rated less than 3 hours, and 3 hours minimum for penetrations of assemblies rated 3 hours or greater. (Table 717.3.2.1 / § 717.3.2.1.)

Quick decision table

Assembly / Location Damper type required Key thresholds / dimensions Code Reference
Fire wall (permitted penetrations) Fire damper per listing; see connection to § 706.11 § 717.5.1
Fire wall that serves as horizontal exit Smoke damper (listed, resists smoke) — § 717.5.1.1
Fire barrier (typical)** Fire damper exceptions apply (ASTM E119 test, smoke control systems, fully ducted HVAC exception, etc.) § 717.5.2
Shaft enclosures (ducts allowed to penetrate) Fire & smoke dampers (listed) Continuous upward airflow exception (no dampers where closure defeats airflow) § 717.5.3 & exceptions
Corridor enclosures requiring smoke/draft control doors Smoke damper (listed) Corridor/corridor ceiling conditions; steel duct exceptions § 717.5.4.1
Smoke barriers / smoke partitions / smoke‑protected corridors Smoke damper smoke damper actuation per § 717.3.3.2 § 717.5.5 / § 717.5.7
Exterior fire‑resistance‑rated walls (protected openings) Fire damper — § 717.5.6

(References: see § 717.5.1, § 717.5.2 and damper rating table § 717.3.2.1.)

Exceptions & special cases

The code includes several important exceptions where dampers are not required — read them closely and confirm with the AHJ:

  • Penetrations that are part of a tested fire‑resistance assembly (ASTM E119 / UL 263) need not use dampers if the test shows the assembly maintains rating without dampers. (Exception in § 717.5.2.)

  • Ducts used as part of an approved mechanical smoke control system (Section 909) where a damper would interfere with the system operation: use approved alternate protection or none if system design requires it. § 717.2.1 and relevant exceptions in § 717.5.x.

  • Shafts: fire dampers are not required at penetrations of shafts when specific criteria are met — for example, where steel exhaust subducts (minimum 0.0187 inch / No. 26 gage) extend not less than 22 inches (559 mm) vertically in exhaust shafts and an exhaust fan at the top of the shaft maintains continuous upward airflow per Section 909.11. Also, fire/smoke dampers shall not be installed where closure would defeat a required continuous upward airflow. See § 717.5.3 exceptions and § 717.5.3.1.

  • Fully ducted HVAC exception: For some fire barriers (limited occupancies/ratings), fire dampers are not required where the wall is penetrated by a fully ducted HVAC system constructed of sheet steel No. 26 gage continuous from the air handling unit to the terminals, and the building meets defined sprinkler/occupancy criteria. See the exception in § 717.5.2.

  • Corridor / steel duct exceptions: Smoke dampers may not be required at corridor penetrations where the duct is steel not less than 0.019 inch (0.48 mm) and there are no openings serving the corridor—see § 717.5.4.1 exceptions.

  • Mechanical code conflicts: some kitchen and dryer exhaust systems prohibit dampers by mechanical code; where so, the Building Code exception removes the damper requirement. See the exceptions in § 717.5.3 and related cross‑reference to the California Mechanical Code.

Always verify whether the project is within the Office of the State Fire Marshal (SFM) scope — SFM regulations require dampers in some occupancies (Groups A, E, H, I, L and R, high‑rise, etc.) even where other exceptions might apply; the code text flags SFM‑regulated cases.

Common mistakes

  • Assuming every duct through a rated wall needs a damper. (Some tested assemblies, fully ducted HVAC exceptions, and other conditions remove the damper requirement — see § 717.5.2 exceptions.)
  • Installing a damper that will defeat a required smoke‑control airflow (e.g., shaft upward airflow). If closure would stop required airflow, the code forbids installing dampers that would defeat the system; use approved alternatives. § 717.5.3.1 and § 717.2.1.
  • Failing to match damper rating to the assembly rating — use Table 717.3.2.1: 1.5 hr for <3‑hr assemblies; 3 hr for ≥3‑hr assemblies.
  • Overlooking access/labeling/testing requirements (access openings, identification, periodic testing per NFPA 80/NFPA 105). See Section 717.4 and the California Mechanical Code testing/installation rules.
  • Not coordinating with the Mechanical Code and the project smoke control rational analysis (Section 909) — dampers may be excluded where they interfere with smoke control. § 717.2.1 and § 909.

Worked example — concrete scenario

Scenario: A rated corridor fire barrier (required rating 1.5 hours) separates two tenant spaces in a mid‑rise office (not SFM‑regulated). A supply duct (metal) penetrates that fire barrier to serve the tenant space. The duct is conventional sheet metal (No. 24 gage), not part of a fully ducted HVAC continuous run qualifying for the exception.

Step 1 — Which § applies? This is a fire barrier penetration: § 717.5.2 applies.
Step 2 — Damper type required? Fire damper (listed) must be provided at the penetration per § 717.5.2.
Step 3 — Damper rating? Table 717.3.2.1 requires a minimum damper rating of 1.5 hours for penetrations of assemblies rated less than 3 hours — that applies here (1.5‑hr wall). Provide a 1.5‑hour listed fire damper installed per the listing.
Step 4 — Check exceptions: the duct is not a fully ducted No. 26 gage continuous system and not part of a tested assembly, and it’s not part of a smoke control system — so no exception applies. Provide access, labeling and arrange for NFPA testing/inspection per § 717.4 and mechanical code requirements.

Result: Install a listed 1.5‑hour fire damper at the penetration, with required access, labeling and periodic testing.

Related provisions (other CFC/CBC/CMC sections to check)

  • § 717.5.1 — Fire walls: ducts / air‑transfer openings in fire walls must have fire dampers (ties to § 706.11).
  • § 717.5.2 — Fire barriers: primary rule for fire damper requirements and exceptions.
  • § 717.3.2.1 (Table 717.3.2.1) — Damper minimum fire ratings (1.5 hr / 3 hr).
  • § 717.2.1 — Interaction with required smoke control systems (Section 909).
  • § 717.4 — Access and identification requirements for dampers (access size, labeling).
  • § 717.5.3 & § 717.5.3.1 — Shaft enclosures and the continuous upward airflow exceptions.
  • California Mechanical Code: fire damper installation, combination damper behavior, testing and inspection (e.g., 606.2, 606.4, 606.6) — coordinate mechanical requirements.
  • Section 909 (smoke control systems) — if ducts are part of an engineered smoke control system, the rational analysis and testing requirements govern damper use.

If you want, I can produce a short checklist you can use at plan review (questions to ask: occupancy group, fire‑resistance rating of the assembly, is duct part of smoke control, duct construction gauge/continuity, is penetration tested assembly, shaft continuous airflow) and a downloadable quick reference table for inspectors/contractors.

Code references

Grounded in the retrieved California Fire Code — click a citation to read the verbatim passage:

  • CFC § 717.5.2.1 High relevance — show source text

    2. Fire and smoke dampers are not required where ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire or smoke damper would interfere with the operation of a smoke control system.

    717.5.2.1 Horizontal exits. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a fire barrier that serves as a horizontal exit.

    717.5.3 Shaft enclosures. Shaft enclosures that are permitted to be penetrated by ducts and air transfer openings shall be protected with listed fire and smoke dampers installed in accordance with their listing.

    Exceptions:

    1. Fire dampers are not required at penetrations of shafts where any of the following criteria are met: 1.1. Steel exhaust subducts having a wall thickness of not less than 0.0187 inch (0.4712 mm) are extended not less than 22 inches (559 mm) vertically in exhaust shafts, and an exhaust fan is installed at the upper terminus of the shaft that is powered continuously in accordance with Section 909.11, so as to maintain a continuous upward airflow to the outdoors. 1.2. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly. 1.3. Ducts are used as part of an approved smoke control system designed and installed in accordance with Section 909 and where the fire damper will interfere with the operation of the smoke control system. 1.4. The penetrations are in parking garage exhaust or supply shafts that are separated from other building shafts by not less than 2-hour fire-resistance-rated construction.
    2. In Group B and R occupancies equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, smoke dampers are not required at penetrations of shafts where all of the following criteria are met: 2.1. Kitchen, clothes dryer, bathroom and toilet room exhaust openings are installed with steel exhaust subducts, having a wall thickness of not less than 0.0187 inch (0.4712 mm). 2.2. The subducts extend not less than 22 inches (559 mm) vertically. 2.3. An exhaust fan is installed at the upper terminus of the shaft that is powered continuously in accordance with the provisions of Section 909.11, so as to maintain a continuous upward airflow to the outdoors.
    3. Smoke dampers are not required at penetration of exhaust or supply shafts in parking garages that are separated from other building shafts by not less than 2-hour fire-resistance-rated construction.
    4. Smoke dampers are not required at penetrations of shafts where ducts are used as part of an approved mechanical smoke control system designed in accordance with Section 909 and where the smoke damper will interfere with the operation of the smoke control system.
    5. Fire dampers and combination fire/smoke dampers are not required in kitchen and clothes dryer exhaust systems where dampers are prohibited by the California Mechanical Code .

    717.5.3.1 Continuous upward airflow. Fire dampers and smoke dampers shall not be installed in shafts that are required to maintain a continuous upward airflow path where closure of the damper would result in the loss of the airflow.

  • CFC § 3.1. High relevance — show source text

    For the purposes of this exception, a fully ducted HVAC system shall be a duct system for conveying supply, return or exhaust air as part of the structure’s HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous from the air-handling appliance or equipment to the air outlet and inlet terminals. Nonmetal flexible air connectors shall be permitted in the following locations in accordance with Section 603 of the California Mechanical Code: 3.1. At the duct connection to the air handling unit or equipment located within the mechanical room. 3.2. From an overhead metal duct to a ceiling diffuser within the same room.

    [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings of fire barriers shall be protected with approved fire and smoke dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate exit enclosures and exit passageways except as permitted by Sections 1023.5 and 1024.6, respectively.

    Exceptions: 1. Fire dampers are not required at penetrations of fire barriers where penetrations are tested in accordance with ASTM E119 as part of the fire-resistance rated assembly.

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    FIRE AND SMOKE PROTECTION FEATURES

    2. Fire and smoke dampers are not required where ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire or smoke damper would interfere with the operation of a smoke control system.

    717.5.2.1 Horizontal exits. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a fire barrier that serves as a horizontal exit.

    717.5.3 Shaft enclosures. Shaft enclosures that are permitted to be penetrated by ducts and air transfer openings shall be protected with listed fire and smoke dampers installed in accordance with their listing.

    Exceptions:

    1. Fire dampers are not required at penetrations of shafts where any of the following criteria are met: 1.1. Steel exhaust subducts having a wall thickness of not less than 0.0187 inch (0.4712 mm) are extended not less than 22 inches (559 mm) vertically in exhaust shafts, and an exhaust fan is installed at the upper terminus of the shaft that is powered continuously in accordance with Section 909.11, so as to maintain a continuous upward airflow to the outdoors. 1.2. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly. 1.3. Ducts are used as part of an approved smoke control system designed and installed in accordance with Section 909 and where the fire damper will interfere with the operation of the smoke control system. 1.4. The penetrations are in parking garage exhaust or supply shafts that are separated from other building shafts by not less than 2-hour fire-resistance-rated construction.
  • CFC § 717.5.1 High relevance — show source text

    717.5.1 Fire walls. Ducts and air transfer openings permitted in fire walls in accordance with Section 706.11 shall be protected with listed fire dampers installed in accordance with their listing.

    717.5.1.1 Horizontal exits. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a fire wall that serves as a horizontal exit.

    717.5.2 Fire barriers. In other than Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal. Ducts and air transfer openings of fire barriers shall be protected with listed fire dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate enclosures for interior exit stairways and ramps and exit passageways, except as permitted by Sections 1023.5 and 1024.6, respectively.

    Exceptions: Fire dampers are not required at penetrations of fire barriers where any of the following apply:

    1. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly.
    2. Ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire damper would interfere with the operation of a smoke control system.
    3. Such walls are penetrated by fully ducted HVAC systems, have a required fire-resistance rating of 1 hour or less, are in areas of other than Group H and are in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. For the purposes of this exception, a fully ducted HVAC system shall be a duct system for conveying supply, return or exhaust air as part of the structure’s HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous from the air-handling appliance or equipment to the air outlet and inlet terminals. Nonmetal flexible air connectors shall be permitted in the following locations in accordance with Section 603 of the California Mechanical Code: 3.1. At the duct connection to the air handling unit or equipment located within the mechanical room. 3.2. From an overhead metal duct to a ceiling diffuser within the same room.

    [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings of fire barriers shall be protected with approved fire and smoke dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate exit enclosures and exit passageways except as permitted by Sections 1023.5 and 1024.6, respectively.

    Exceptions: 1. Fire dampers are not required at penetrations of fire barriers where penetrations are tested in accordance with ASTM E119 as part of the fire-resistance rated assembly.

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  • CFC § 1.4. High relevance — show source text

    1.4. The penetrations are in parking garage exhaust or supply shafts that are separated from other building shafts by not less than 2-hour fire-resistance-rated construction. 2. In Group B and R occupancies equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, smoke dampers are not required at penetrations of shafts where all of the following criteria are met: 2.1. Kitchen, clothes dryer, bathroom and toilet room exhaust openings are installed with steel exhaust subducts, having a wall thickness of not less than 0.0187 inch (0.4712 mm). 2.2. The subducts extend not less than 22 inches (559 mm) vertically. 2.3. An exhaust fan is installed at the upper terminus of the shaft that is powered continuously in accordance with the provisions of Section 909.11, so as to maintain a continuous upward airflow to the outdoors. 3. Smoke dampers are not required at penetration of exhaust or supply shafts in parking garages that are separated from other building shafts by not less than 2-hour fire-resistance-rated construction. 4. Smoke dampers are not required at penetrations of shafts where ducts are used as part of an approved mechanical smoke control system designed in accordance with Section 909 and where the smoke damper will interfere with the operation of the smoke control system. 5. Fire dampers and combination fire/smoke dampers are not required in kitchen and clothes dryer exhaust systems where dampers are prohibited by the California Mechanical Code .

    717.5.3.1 Continuous upward airflow. Fire dampers and smoke dampers shall not be installed in shafts that are required to maintain a continuous upward airflow path where closure of the damper would result in the loss of the airflow.

    717.5.4 Fire partitions. In other than Group A, E, I and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings that penetrate fire partitions shall be protected with listed fire dampers installed in accordance with their listing.

    Exceptions: In occupancies other than Group H and L, fire dampers are not required where any of the following apply:

    1. Corridor walls in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2 and the duct is protected as a through penetration in accordance with Section 714.
    2. Tenant partitions in covered and open mall buildings where the walls are not required by provisions elsewhere in the code to extend to the underside of the floor or roof sheathing, slab or deck above.
    3. The duct system is constructed of approved materials in accordance with the California Mechanical Code and the duct penetrating the wall complies with all of the following requirements: 3.1. The duct shall not exceed 100 square inches (0.06 m [2] ). 3.2. The duct shall be constructed of steel not less than 0.0217 inch (0.55 mm) in thickness.

    3.3. The duct shall not have openings that communicate the corridor with adjacent spaces or rooms. 3.4. The duct shall be installed above a ceiling. 3.5. The duct shall not terminate at a wall register in the fire-resistance-rated wall. 3.6. A minimum 12-inch-long (305 mm) by 0.060-inch-thick (1.52 mm) steel sleeve shall be centered in each duct opening.

  • CFC § 0.060 High relevance — show source text

    2. The sleeve shall be secured to both sides of the wall and for all four sides of the sleeve with minimum 1 [1] / 2 -inch by 1 [1] / 2 -inch by 0.060-inch (38 mm by 38 mm by 1.52 mm) steel retaining angles. 3. The retaining angles shall be secured to the sleeve and the wall with No. 10 (M5) screws. 4. The annular space between the steel sleeve and the wall opening shall be filled with mineral wool batting on all sides.

    717.5.4.1 Corridors. In other than Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, duct and air transfer openings that penetrate corridors shall be protected with dampers as follows:

    1. A corridor damper shall be provided where corridor ceilings, constructed as required for the corridor walls as permitted in Section 708.4, Exception 3, are penetrated.
    2. A ceiling radiation damper shall be provided where the ceiling membrane of a fire-resistance-rated floor-ceiling or roof-ceiling assembly, constructed as permitted in Section 708.4, Exception 2, is penetrated.
    3. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a corridor enclosure required to have smoke and draft control doors in accordance with Section 716.2.2.1.

    Exceptions:

    1. Smoke dampers are not required where the building is equipped throughout with an approved smoke control system in accordance with Section 909, and smoke dampers are not necessary for the operation and control of the system.
    2. Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor.

    [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, a listed smoke damper designed to resist the passage of smoke shall also be provided at each point a duct or air transfer opening penetrates a fire-resistance rated corridor enclosure required to have smoke and draft doors in accordance with Section 716.2.2.1 or doors that provide an effective barrier to limit the transfer of smoke in accordance with Section 407.3.1.

    Exceptions: 1. Smoke dampers are not required where ducts are used as part of an approved mechanical smoke control system designed in accordance with Section 909 and where the smoke damper will interfere with the operation of the smoke control system. 2. Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor. 717.5.5 Smoke barriers. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a smoke barrier. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

  • CFC § 606.2 High relevance — show source text

    606.2 Fire Dampers. Fire dampers shall comply with UL 555, and shall be installed in accordance with the manufacturer’s installation instructions where required by the building code. Fire dampers shall have been tested for closure under airflow conditions and shall be labeled for both maximum airflow permitted and direction of flow. Where more than one damper is installed at a point in a single air path, the entire airflow shall be assumed to be passing through the smallest damper area.

    Ductwork shall be connected to damper sleeves or assemblies in accordance with the fire damper manufacturer’s installation instructions.

    606.3 Ceiling Radiation Dampers. Ceiling radiation dampers shall comply with UL 555C or shall be tested as part of a fire-resistance-rated floor-ceiling or roof-ceiling assembly in accordance with ASTM E119 or UL 263, and shall be installed in accordance with the manufacturer’s installation instructions in the fire-resistive ceiling membrane of floorceiling and roof-ceiling assemblies where required by the building code. Fire dampers not meeting the temperature limitation of ceiling radiation dampers shall not be used as a substitute.

    606.4 Combination Fire/Smoke Dampers. Combination fire/smoke dampers shall comply with UL 555 and UL 555S and the requirements in Section 606.1 and Section 606.2.

    606.4.1 When the automatic activation of a smoke damper or a combination smoke-fire damper occurs, the HVAC system serving such dampers shall immediately shut down.

    Exceptions:

    (1) HVAC systems that are part of an engineered smoke evacuation system.

    (2) Where the automatic activation causes all the smoke dampers and combination smoke-fire dampers to close in the enclosed space having a common atmos- phere where openings are required to be protected.

    (3) Where analysis demonstrates shutoff would create a greater hazard.

    The HVAC system shall not be restarted again until all the dampers are reset and fully opened. 606.5 Corridor Dampers. Corridor dampers shall comply with the requirements of combination fire/smoke dampers in Section 606.4.

    606.6 Periodic Testing and Inspection. Testing and inspection of dampers shall be in accordance with the following:

    (1) Smoke dampers shall be tested in accordance with NFPA 105.

    (2) Fire dampers shall be tested in accordance with NFPA 80.

    (3) Combination fire/smoke dampers shall be tested in accordance with NFPA 80 and NFPA 105.

    606.7 Multiple Arrangements. Where size requires the use of multiple dampers, each damper shall be listed for use in multiple arrangements and installed in accordance with the manufacturer’s installation instructions.

    606.8 Access and Identification. Fire and smoke

    dampers shall be provided with an approved means of access large enough to allow inspection and maintenance of the damper and its operating parts. The access shall not affect the integrity of the fire-resistance-rated assembly. The access openings shall not reduce the fire-resistance rating of the assembly.

    Access shall not require the use of tools. Access doors in ducts shall be tight fitting and approved for the required duct construction. Access points shall be permanently identified on the exterior by a label with letters not less than [1] ⁄ 2 of an inch (12.7 mm) in height reading as one of the following:

    (1) Smoke Damper

    (2) Fire Damper

  • CFC § 0.019 High relevance — show source text

    Exceptions:

    1. Smoke dampers are not required where the building is equipped throughout with an approved smoke control system in accordance with Section 909, and smoke dampers are not necessary for the operation and control of the system.
    2. Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor.

    [SFM] For Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, a listed smoke damper designed to resist the passage of smoke shall also be provided at each point a duct or air transfer opening penetrates a fire-resistance rated corridor enclosure required to have smoke and draft doors in accordance with Section 716.2.2.1 or doors that provide an effective barrier to limit the transfer of smoke in accordance with Section 407.3.1.

    Exceptions: 1. Smoke dampers are not required where ducts are used as part of an approved mechanical smoke control system designed in accordance with Section 909 and where the smoke damper will interfere with the operation of the smoke control system. 2. Smoke dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness and there are no openings serving the corridor. 717.5.5 Smoke barriers. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a smoke barrier. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

    Exception: Smoke dampers are not required where the openings in ducts are limited to a single smoke compartment and the ducts are constructed of steel. � 717.5.6 Exterior walls. Ducts and air transfer openings in fire-resistance-rated exterior walls required to have protected openings in accordance with Section 705.11 shall be protected with listed fire dampers installed in accordance with their listing.

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    717.5.7 Smoke partitions. A listed smoke damper designed to resist the passage of smoke shall be provided at each point that an air transfer opening penetrates a smoke partition. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

    Exception: Where the installation of a smoke damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized.

    717.6 Horizontal assemblies. Penetrations by ducts and air transfer openings of a floor, floor/ceiling assembly or the ceiling membrane of a roof/ceiling assembly shall be protected by a shaft enclosure that complies with Section 713 or shall comply with Sections 717.6.1 through 717.6.3.

  • CFC § 716.3.5.1 High relevance — show source text

    716.3.5.1 Fire window frames. Fire window frames shall be approved for the intended application.

    716.3.5.2 Labeling requirements. Fire-protection-rated glazing shall bear a label or other identification showing the name of the manufacturer, the test standard and information required in Section 716.1.2.2.2 and Table 716.1(3) that shall be issued by an approved agency and permanently identified on the glazing.

    716.3.6 Installation. Fire window assemblies shall be installed in accordance with the provisions of this section.

    716.3.6.1 Closure. Fire-protection-rated glazing shall be in the fixed position or be automatic-closing and shall be installed in labeled frames.

    716.4 Fire protective curtain assembly. Approved fire protective curtain assemblies shall be constructed of any materials or assembly of component materials tested without hose stream in accordance with UL 10D, and shall comply with the Sections 716.4.1 through 716.4.3.

    716.4.1 Label. Fire protective curtain assemblies used as opening protectives in fire-rated walls and smoke partitions shall be labeled in accordance with Section 716.2.9.

    716.4.2 Smoke and draft control. Fire protective curtain assemblies used to protect openings where smoke and draft control assemblies are required shall comply with Section 716.2.1.4.

    716.4.3 Installation. Fire protective curtain assemblies shall be installed in accordance with NFPA 80.

    SECTION 717—DUCTS AND AIR TRANSFER OPENINGS

    717.1 General. The provisions of this section shall govern the protection of duct penetrations and air transfer openings in assemblies required to be protected and duct penetrations in nonfire-resistance-rated floor assemblies.

    717.1.1 Ducts and air transfer openings. Ducts transitioning horizontally between shafts shall not require a shaft enclosure provided that the duct penetration into each associated shaft is protected with dampers complying with this section.

    717.1.2 Ducts that penetrate fire-resistance-rated assemblies without dampers. Ducts that penetrate fire-resistance-rated walls and are not required by this section to have fire dampers shall comply with the requirements of Sections 714.3 through 714.4.3. Ducts that penetrate horizontal assemblies not required to be contained within a shaft and not required by this section to have fire dampers shall comply with the requirements of Sections 714.5 through 714.6.2.

    717.1.2.1 Ducts that penetrate nonfire-resistance-rated assemblies. The space around a duct penetrating a nonfire-resistance-rated floor assembly shall comply with Section 717.6.3.

    717.2 Installation. Fire dampers, smoke dampers, combination fire/smoke dampers and ceiling radiation dampers located within air distribution and smoke control systems shall be installed in accordance with the manufacturer’s instructions, the dampers’ listing and Sections 717.2.1 through 717.2.4.

    717.2.1 Smoke control system. Where the installation of a fire damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized. Where mechanical systems including ducts and dampers utilized for normal building ventilation serve as part of the smoke control system, the expected performance of these systems in smoke control mode shall be addressed in the rational analysis required by Section 909.4.

  • CFC § 717.3.3.5 High relevance — show source text

    717.3.3.5 Corridor damper actuation. Corridor damper actuation shall be in accordance with Sections 717.3.3.1 and 717.3.3.2.

    717.4 Access and identification. Access and identification of fire and smoke dampers shall comply with Sections 717.4.1 through 717.4.2.

    717.4.1 Access. Fire and smoke dampers shall be provided with an approved means of access that is large enough to permit inspection and maintenance of the damper and its operating parts. Dampers equipped with fusible links, internal operators, or both shall be provided with an access door that is not less than 12 inches (305 mm) square or provided with a removable duct section.

    717.4.1.1 Access openings. The access shall not affect the integrity of fire-resistance-rated assemblies. The access openings shall not reduce the fire-resistance rating of the assembly. Access doors in ducts shall be tight fitting and suitable for the required duct construction.

    717.4.1.2 Restricted access. Where space constraints or physical barriers restrict access to a damper for periodic inspection and testing, the damper shall be a single- or multi-blade type damper and shall comply with the remote inspection requirements of NFPA 80 or NFPA 105.

    717.4.2 Identification. Access points shall be permanently identified on the exterior by a label having letters not less than [1] / 2 inch (12.7 mm) in height reading: “FIRE/SMOKE DAMPER,” “SMOKE DAMPER” or “FIRE DAMPER.”

    717.5 Where required. Fire dampers, smoke dampers, combination fire/smoke dampers, ceiling radiation dampers and corridor dampers shall be provided at the locations prescribed in Sections 717.5.1 through 717.5.7 and 717.6. Where an assembly is required to have both fire dampers and smoke dampers, combination fire/smoke dampers or a fire damper and a smoke damper shall be provided.

    717.5.1 Fire walls. Ducts and air transfer openings permitted in fire walls in accordance with Section 706.11 shall be protected with listed fire dampers installed in accordance with their listing.

    717.5.1.1 Horizontal exits. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a fire wall that serves as a horizontal exit.

    717.5.2 Fire barriers. In other than Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal. Ducts and air transfer openings of fire barriers shall be protected with listed fire dampers installed in accordance with their listing. Ducts and air transfer openings shall not penetrate enclosures for interior exit stairways and ramps and exit passageways, except as permitted by Sections 1023.5 and 1024.6, respectively.

    Exceptions: Fire dampers are not required at penetrations of fire barriers where any of the following apply:

    1. Penetrations are tested in accordance with ASTM E119 or UL 263 as part of the fire-resistance-rated assembly.
    2. Ducts are used as part of an approved smoke control system in accordance with Section 909 and where the use of a fire damper would interfere with the operation of a smoke control system.
  • CFC § 717.1.1 High relevance — show source text

    717.1.1 Ducts and air transfer openings. Ducts transitioning horizontally between shafts shall not require a shaft enclosure provided that the duct penetration into each associated shaft is protected with dampers complying with this section.

    717.1.2 Ducts that penetrate fire-resistance-rated assemblies without dampers. Ducts that penetrate fire-resistance-rated walls and are not required by this section to have fire dampers shall comply with the requirements of Sections 714.3 through 714.4.3. Ducts that penetrate horizontal assemblies not required to be contained within a shaft and not required by this section to have fire dampers shall comply with the requirements of Sections 714.5 through 714.6.2.

    717.1.2.1 Ducts that penetrate nonfire-resistance-rated assemblies. The space around a duct penetrating a nonfire-resistance-rated floor assembly shall comply with Section 717.6.3.

    717.2 Installation. Fire dampers, smoke dampers, combination fire/smoke dampers and ceiling radiation dampers located within air distribution and smoke control systems shall be installed in accordance with the manufacturer’s instructions, the dampers’ listing and Sections 717.2.1 through 717.2.4.

    717.2.1 Smoke control system. Where the installation of a fire damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized. Where mechanical systems including ducts and dampers utilized for normal building ventilation serve as part of the smoke control system, the expected performance of these systems in smoke control mode shall be addressed in the rational analysis required by Section 909.4.

    717.2.2 Hazardous exhaust ducts. Fire dampers for hazardous exhaust duct systems shall comply with the California Mechanical Code .

    717.2.3 Static dampers. Fire dampers and ceiling radiation dampers that are listed for use in static systems shall only be installed in heating, ventilation and air-conditioning systems that are automatically shut down in the event of a fire.

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    717.2.4 Mechanical, electrical and plumbing controls. Mechanical, electrical and plumbing controls shall not be installed in air duct systems.

    Exception: Controls where the wiring is directly associated with the air distribution system. The wiring shall comply with the requirements of Section 601 of the California Mechanical Code and be as short as practicable.

    717.2.4.1 Controls not permitted to be installed through dampers. Mechanical, electrical and plumbing controls shall not be installed through fire dampers, smoke dampers, combination fire/smoke dampers or ceiling radiation dampers unless otherwise permitted by the manufacturer and the listing.

    717.3 Damper testing, ratings and actuation. Damper testing, ratings and actuation shall be in accordance with Sections 717.3.1 through 717.3.3.

    717.3.1 Damper testing. Dampers shall be listed and labeled in accordance with the standards in this section.

    1. Fire dampers shall comply with the requirements of UL 555.
    2. Smoke dampers shall comply with the requirements of UL 555S.
    3. Combination fire/smoke dampers shall comply with the requirements of both UL 555 and UL 555S.
  • CFC § 717.2.3 Medium relevance — show source text

    717.2.3 Static dampers. Fire dampers and ceiling radiation dampers that are listed for use in static systems shall only be installed in heating, ventilation and air-conditioning systems that are automatically shut down in the event of a fire.

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    717.2.4 Mechanical, electrical and plumbing controls. Mechanical, electrical and plumbing controls shall not be installed in air duct systems.

    Exception: Controls where the wiring is directly associated with the air distribution system. The wiring shall comply with the requirements of Section 601 of the California Mechanical Code and be as short as practicable.

    717.2.4.1 Controls not permitted to be installed through dampers. Mechanical, electrical and plumbing controls shall not be installed through fire dampers, smoke dampers, combination fire/smoke dampers or ceiling radiation dampers unless otherwise permitted by the manufacturer and the listing.

    717.3 Damper testing, ratings and actuation. Damper testing, ratings and actuation shall be in accordance with Sections 717.3.1 through 717.3.3.

    717.3.1 Damper testing. Dampers shall be listed and labeled in accordance with the standards in this section.

    1. Fire dampers shall comply with the requirements of UL 555.
    2. Smoke dampers shall comply with the requirements of UL 555S.
    3. Combination fire/smoke dampers shall comply with the requirements of both UL 555 and UL 555S.
    4. Ceiling radiation dampers shall comply with the requirements of UL 555C or shall be tested as part of a fire-resistancerated floor/ceiling or roof/ceiling assembly in accordance with ASTM E119 or UL 263.
    5. Corridor dampers shall comply with requirements of both UL 555 and UL 555S. Corridor dampers shall demonstrate acceptable closure performance when subjected to 150 feet per minute (0.76 mps) velocity across the face of the damper during the UL 555 fire exposure test.

    717.3.2 Damper rating. Damper ratings shall be in accordance with Sections 717.3.2.1 through 717.3.2.4.

    717.3.2.1 Fire damper ratings. Fire dampers shall have the minimum rating specified in Table 717.3.2.1.

    TABLE 717.3.2.1—FIRE DAMPER RATING Col2
    TYPE OF PENETRATION MINIMUM DAMPER RATING (hours)
    Less than 3-hour fire-resistance-rated assemblies 1.5
    3-hour or greater fire-resistance-rated assemblies 3

    717.3.2.2 Smoke damper ratings. Smoke damper leakage ratings shall be Class I or II. Elevated temperature ratings shall be not less than 250°F (121°C).

    717.3.2.3 Combination fire/smoke damper ratings. Combination fire/smoke dampers shall have the minimum rating specified for fire dampers in Table 717.3.2.1 and shall have the minimum rating specified for smoke dampers in Section 717.3.2.2.

  • CFC § 714.5.2 Medium relevance — show source text

    1. A shaft enclosure in accordance with Section 713.

    2. A listed ceiling radiation damper installed at the ceiling line where a duct penetrates the ceiling of a fire-resistance-rated floor/ceiling or roof/ceiling assembly. Exceptions:

    3. A fire-resistance-rated assembly tested in accordance with ASTM E119 or UL 263 showing that ceiling radiation dampers are not required in order to maintain the fire-resistance rating of the assembly.

    4. Where exhaust duct or outdoor air duct penetrations protected in accordance with Section 714.5.2 are located within the cavity of a wall and do not pass through another dwelling unit or tenant space.

    5. Where duct and air transfer openings are protected with a duct outlet penetration system tested as part of a fire-resistance-rated assembly in accordance with ASTM E119 or UL 263.

    6. A listed ceiling radiation damper installed at the ceiling line where a diffuser with no duct attached penetrates the ceiling of a fire-resistance-rated floor/ceiling or roof/ceiling assembly. Exceptions:

    7. A fire-resistance-rated assembly tested in accordance with ASTM E119 or UL 263 showing that ceiling radiation dampers are not required in order to maintain the fire-resistance rating of the assembly.

    8. Where duct and air transfer openings are protected with a duct outlet penetration system tested as part of a fire-resistance-rated assembly in accordance with ASTM E119 or UL 263.

    717.6.2.1 Ceiling radiation dampers testing and installation. Ceiling radiation dampers shall be tested in accordance with Section 717.3.1. Ceiling radiation dampers shall be installed in accordance with the details specified in the fire-resistance-rated assembly and the manufacturer’s instructions and the listing.

    717.6.2.1.1 Dynamic systems. Only ceiling radiation dampers labeled for use in dynamic systems shall be installed in heating, ventilation and air-conditioning systems designed to operate with fans on during a fire.

    717.6.2.1.2 Static systems. Static ceiling radiation dampers shall be provided with systems that are not designed to operate during a fire.

    Exceptions:

    1. Where a static ceiling radiation damper is installed at the opening of a duct, a smoke detector shall be installed inside the duct or outside the duct with sampling tubes protruding into the duct. The detector or tubes in the duct shall be within 5 feet (1524 mm) of the damper. Air outlets and inlets shall not be located between the detector or tubes and the damper. The detector shall be listed for the air velocity, temperature and humidity

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    anticipated at the point where it is installed. Other than in mechanical smoke control systems, dampers shall be closed upon fan shutdown where local smoke detectors require a minimum velocity to operate. 2. Where a static ceiling radiation damper is installed in a ceiling, the ceiling radiation damper shall be permitted to be controlled by a smoke detection system installed in the same room or area as the ceiling radiation damper. 3. A static ceiling radiation damper shall be permitted to be installed in a room where an occupant sensor is provided within the room that will shut down the system.

    717.6.3 Nonfire-resistance-rated floor assemblies. Duct systems constructed of approved materials in accordance with the California Mechanical Code that penetrate nonfire-resistance-rated floor assemblies shall be protected by any of the following methods:

  • CFC § 1.11 High relevance — show source text

    For Group A, E, I and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings that penetrate fire partitions shall be protected with listed fire dampers installed in accordance with their listings.

    Exceptions: 1. Fire dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness, protected as a through penetration in accordance with Section 713 and there are no openings serving the corridor.

    2. Fire dampers are not required where the duct system is constructed of approved materials in accordance with the Cali- fornia Mechanical Code and the duct penetrating the wall complies with all of the following requirements: 2.1. For other than corridors in Group I-2 occupancies the duct shall not exceed 100 square inches (0.6 m [2] ). 2.2. The duct shall be constructed of steel a minimum of 0.0217 inch (0.55 mm) in thickness.

    2.3. The duct shall not have openings that communicate the corridor with adjacent spaces or rooms. 2.4. The duct shall be installed above a ceiling. 2.5. The duct shall not terminate at a wall register in the fire-resistance rated wall. 2.6. The duct shall be protected as a through penetration in accordance with Section 714 or shall comply with all of the following: 1. A minimum 12-inch-long (305 mm) by 0.060-inch-thick (1.52 mm) steel sleeve shall be centered in each duct opening.

    2. The sleeve shall be secured to both sides of the wall and for all four sides of the sleeve with minimum 1 [1] / 2 -inch by 1 [1] / 2 -inch by 0.060-inch (38 mm by 38 mm by 1.52 mm) steel retaining angles. 3. The retaining angles shall be secured to the sleeve and the wall with No. 10 (M5) screws. 4. The annular space between the steel sleeve and the wall opening shall be filled with mineral wool batting on all sides.

    717.5.4.1 Corridors. In other than Group A, E, H, I, L and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, duct and air transfer openings that penetrate corridors shall be protected with dampers as follows:

    1. A corridor damper shall be provided where corridor ceilings, constructed as required for the corridor walls as permitted in Section 708.4, Exception 3, are penetrated.
    2. A ceiling radiation damper shall be provided where the ceiling membrane of a fire-resistance-rated floor-ceiling or roof-ceiling assembly, constructed as permitted in Section 708.4, Exception 2, is penetrated.
    3. A listed smoke damper designed to resist the passage of smoke shall be provided at each point a duct or air transfer opening penetrates a corridor enclosure required to have smoke and draft control doors in accordance with Section 716.2.2.1.

    Exceptions:

  • CFC § 717.5.4 Medium relevance — show source text

    717.5.4 Fire partitions. In other than Group A, E, I and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings that penetrate fire partitions shall be protected with listed fire dampers installed in accordance with their listing.

    Exceptions: In occupancies other than Group H and L, fire dampers are not required where any of the following apply:

    1. Corridor walls in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2 and the duct is protected as a through penetration in accordance with Section 714.
    2. Tenant partitions in covered and open mall buildings where the walls are not required by provisions elsewhere in the code to extend to the underside of the floor or roof sheathing, slab or deck above.
    3. The duct system is constructed of approved materials in accordance with the California Mechanical Code and the duct penetrating the wall complies with all of the following requirements: 3.1. The duct shall not exceed 100 square inches (0.06 m [2] ). 3.2. The duct shall be constructed of steel not less than 0.0217 inch (0.55 mm) in thickness.

    3.3. The duct shall not have openings that communicate the corridor with adjacent spaces or rooms. 3.4. The duct shall be installed above a ceiling. 3.5. The duct shall not terminate at a wall register in the fire-resistance-rated wall. 3.6. A minimum 12-inch-long (305 mm) by 0.060-inch-thick (1.52 mm) steel sleeve shall be centered in each duct opening. The sleeve shall be secured to both sides of the wall and all four sides of the sleeve with minimum 1 [1] / 2 -inch by 1 [1] / 2 -inch by 0.060-inch (38 mm by 38 mm by 1.52 mm) steel retaining angles. The retaining angles shall be secured to the sleeve and the wall with No. 10 (M5) screws. The annular space between the steel sleeve and the wall opening shall be filled with mineral wool batting on all sides. 4. Such walls are penetrated by ducted HVAC systems, have a required fire-resistance rating of 1 hour or less, and are in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. For the purposes of this exception, a ducted HVAC system shall be a duct system for conveying supply, return or

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    exhaust air as part of the structure’s HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous from the air-handling appliance or equipment to the air outlet and inlet terminals.

    For Group A, E, I and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings that penetrate fire partitions shall be protected with listed fire dampers installed in accordance with their listings.

  • CFC § 0.060 Medium relevance — show source text

    The sleeve shall be secured to both sides of the wall and all four sides of the sleeve with minimum 1 [1] / 2 -inch by 1 [1] / 2 -inch by 0.060-inch (38 mm by 38 mm by 1.52 mm) steel retaining angles. The retaining angles shall be secured to the sleeve and the wall with No. 10 (M5) screws. The annular space between the steel sleeve and the wall opening shall be filled with mineral wool batting on all sides. 4. Such walls are penetrated by ducted HVAC systems, have a required fire-resistance rating of 1 hour or less, and are in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2. For the purposes of this exception, a ducted HVAC system shall be a duct system for conveying supply, return or

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    exhaust air as part of the structure’s HVAC system. Such a duct system shall be constructed of sheet steel not less than No. 26 gage thickness and shall be continuous from the air-handling appliance or equipment to the air outlet and inlet terminals.

    For Group A, E, I and R occupancies, high-rise buildings, and other applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, ducts and air transfer openings that penetrate fire partitions shall be protected with listed fire dampers installed in accordance with their listings.

    Exceptions: 1. Fire dampers are not required in corridor penetrations where the duct is constructed of steel not less than 0.019 inch (0.48 mm) in thickness, protected as a through penetration in accordance with Section 713 and there are no openings serving the corridor.

    2. Fire dampers are not required where the duct system is constructed of approved materials in accordance with the Cali- fornia Mechanical Code and the duct penetrating the wall complies with all of the following requirements: 2.1. For other than corridors in Group I-2 occupancies the duct shall not exceed 100 square inches (0.6 m [2] ). 2.2. The duct shall be constructed of steel a minimum of 0.0217 inch (0.55 mm) in thickness.

    2.3. The duct shall not have openings that communicate the corridor with adjacent spaces or rooms. 2.4. The duct shall be installed above a ceiling. 2.5. The duct shall not terminate at a wall register in the fire-resistance rated wall. 2.6. The duct shall be protected as a through penetration in accordance with Section 714 or shall comply with all of the following: 1. A minimum 12-inch-long (305 mm) by 0.060-inch-thick (1.52 mm) steel sleeve shall be centered in each duct opening.

  • CFC § 717.5.6 Medium relevance — show source text

    Exception: Smoke dampers are not required where the openings in ducts are limited to a single smoke compartment and the ducts are constructed of steel. � 717.5.6 Exterior walls. Ducts and air transfer openings in fire-resistance-rated exterior walls required to have protected openings in accordance with Section 705.11 shall be protected with listed fire dampers installed in accordance with their listing.

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    717.5.7 Smoke partitions. A listed smoke damper designed to resist the passage of smoke shall be provided at each point that an air transfer opening penetrates a smoke partition. Smoke dampers and smoke damper actuation methods shall comply with Section 717.3.3.2.

    Exception: Where the installation of a smoke damper will interfere with the operation of a required smoke control system in accordance with Section 909, approved alternative protection shall be utilized.

    717.6 Horizontal assemblies. Penetrations by ducts and air transfer openings of a floor, floor/ceiling assembly or the ceiling membrane of a roof/ceiling assembly shall be protected by a shaft enclosure that complies with Section 713 or shall comply with Sections 717.6.1 through 717.6.3.

    717.6.1 Through penetrations. A duct constructed of approved materials in accordance with the California Mechanical Code that penetrates a fire-resistance-rated floor/ceiling assembly that connects not more than two stories is permitted without shaft enclosure protection, provided that a listed fire damper is installed at the floor line or the duct is protected in accordance with Section 714.5. For air transfer openings, see Section 712.1.9.

    Exception: In occupancies other than Groups I-2 and I-3, a duct is permitted to penetrate three floors or less without a fire damper at each floor, provided that such duct meets all of the following requirements:

    1. The duct shall be contained and located within the cavity of a wall and shall be constructed of steel having a minimum wall thickness of 0.0187 inches (0.4712 mm) (No. 26 gage).
    2. The duct shall open into only one dwelling unit or sleeping unit and the duct system shall be continuous from the unit to the exterior of the building.
    3. The duct shall not exceed 4-inch (102 mm) nominal diameter and the total area of such ducts shall not exceed 100 square inches (0.065 m [2] ) in any 100 square feet (9.3 m [2] ) of floor area.
    4. The annular space around the duct is protected with materials that prevent the passage of flame and hot gases sufficient to ignite cotton waste where subjected to ASTM E119 or UL 263 time-temperature conditions under a minimum positive pressure differential of 0.01 inch of water (2.49 Pa) at the location of the penetration for the time period equivalent to the fire-resistance rating of the construction penetrated.
    5. Grille openings located in a ceiling of a fire-resistance-rated floor/ceiling or roof/ceiling assembly shall be protected with a listed ceiling radiation damper installed in accordance with Section 717.6.2.1.

Frequently asked questions

When must a smoke damper be used instead of a fire damper?

Use a smoke damper where the penetration is through an assembly that requires smoke control (smoke barriers, smoke partitions, corridors with smoke/draft doors, fire walls that serve as horizontal exits) — see § 717.5.1.1, § 717.5.4.1, § 717.5.5.

Can a listed combination fire/smoke damper satisfy both requirements?

Yes — where an assembly requires both fire and smoke protection, the code permits a combination fire/smoke damper listed for both UL 555 (fire) and UL 555S (smoke), installed per listing. See § 717.5 and the damper testing/ratings sections.

Are there size or material thresholds that remove the damper requirement?

Yes — several exceptions rely on duct construction and size (for example, fully ducted systems constructed of No. 26 gage sheet steel, or corridor ducts of steel ≥ 0.019 inch with no openings). These exceptions are in § 717.5.2 and § 717.5.4.1 — check the exact criteria before omitting a damper.

If a damper closes during smoke control, can the HVAC keep running?

Not normally. Activation of smoke dampers or combination dampers is typically tied to shutting down the HVAC system unless the HVAC is part of an engineered smoke‑evacuation system or specific exceptions apply — see the California Mechanical Code (e.g., 606.4.1). Coordinate with the smoke control design (Section 909).

How do I confirm the required damper rating?

Use Table 717.3.2.1 (minimum fire damper rating: 1.5 hr for <3‑hr assemblies; 3 hr for ≥3‑hr assemblies). Also confirm listing and installation instructions per the damper manufacturer.

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