|Adopt entire chapter||X|
|Adopt entire chapter as
sections listed below)
|Adopt only those sections
that are listed below
|Chapter / Section|
The Office of the State Fire Marshal's adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
[Not permitted for OSHPD 1, 1R, 2, 3, 4 & 5] Concealed building spaces or independent construction within buildings shall be permitted to be used as ducts or plenums. Gypsum board shall not be used for positive pressure ducts.
- Return-air and outside-air ducts, plenums, or concealed spaces that serve a dwelling unit.
- Air filters in accordance with the requirements of Section 311.2.
- Water evaporation media in an evaporative cooler.
- Charcoal filters where protected with an approved fire suppression system.
- Products listed and labeled for installation within plenums in accordance with Section 602.2.1 through Section 602.2.3.
- Smoke detectors.
- Duct insulation, coverings, and linings and other supplementary materials installed in accordance with Section 604.0.
- Materials in a hazardous fabrication area including the areas above and below the fabrication area sharing a common air recirculation path with the fabrication area.
- Shall not prevent access to an area of the crawl space.
- Where it is required to move under ducts for access to areas of the crawl space, a vertical clearance of not less than 18 inches (457 mm) shall be provided.
Metal ducts shall be installed with not less than 4 inches (102 mm) separation from earth. Ducts shall be installed in a building with clearances that will retain the full thickness of fire-proofing on structural members.
Factory-made air ducts shall not be used for vertical risers in air-duct systems serving more than two stories and shall not penetrate a fire-resistance-rated assembly or construction.
Factory-made air ducts shall be installed with not less than 4 inches (102 mm) of separation from earth, except where installed as a liner inside of concrete, tile, or metal pipe and shall be protected from physical damage.
The temperature of the air to be conveyed in a duct shall not exceed 250°F (121° C). Flexible air connectors shall not be permitted.
Flexible air duct installations shall comply with the following:
- Ducts shall be installed using the minimum required length to make the connection.
- Horizontal duct runs shall be supported at not more than 4 feet (1219 mm) intervals.
- Vertical risers shall be supported at not more than 6 feet (1829 mm) intervals.
- Sag between support hangers shall not exceed 1/2 inch (12.7 mm) per foot (305 mm) of support spacing.
- Supports shall be rigid and shall be not less than 11/2 inches (38 mm) wide at point of contact with the duct surface.
- Duct bends shall be not less than one duct diameter bend radius.
- Screws shall not penetrate the inner liner of non-metallic flexible ducts unless permitted in accordance with the manufacturer's installation instructions.
- Fittings for attaching non-metallic ducts shall be beaded
and have a collar length of not less than 2 inches (51 mm)
for attaching the duct.
Exception: A bead shall not be required where metal worm-gear clamps are used or where attaching metallic ducts using screws in accordance with the manufacturer's installation instructions.
- Duct inner liner shall be installed at not less than 1 inch (25.4 mm) on the collar and past the bead prior to the application of the tape and mechanical fastener. Where mastic is used instead of tape, the mastic shall be applied in accordance the mastic manufacturer's instructions.
- Duct outer vapor barriers shall be secured using two wraps of approved tape. A mechanical fastener shall be permitted to be used in place of, or in combination with, the tape.
- Flexible air ducts shall not penetrate a fire-resistance-rated assembly or construction.
- The temperature of the air to be conveyed in a flexible air duct shall not exceed 250°F (121 °C).
- Flexible Air ducts shall be sealed in accordance with Section 603.10.
Factory-made air ducts that are in accordance with UL 181 shall be supported in accordance with the manufacturer's installation instructions. Other ducts shall comply with SMACNA HVAC Duct Construction Standards-Metal and Flexible.
Joints and seams and reinforcements for factory-made air ducts and plenums shall comply with the conditions of prior approval in accordance with the installation instructions that shall accompany the product. Closure systems for sealing factory made air ducts and plenums shall be listed and labeled in accordance with UL 181A or UL 181B, and marked in accordance with Table 603.10.
|TYPE OF DUCTWORK||STANDARD||TYPE OF CLOSURE SYSTEM||MARKING|
|Rigid Metallic or
|UL 181A||Pressure Sensitive Tape||181A-P|
|Rigid Metallic or
|UL 181A||Mastic Tape||181A-M|
|Rigid Metallic or
|UL 181A||Heat Sensitive Tape
|Flexible Air Ducts||UL 181B||Pressure Sensitive Tape*
|Flexible Air Ducts||UL 181B||Mastic*||181B-M*|
|Lmax||=||CLP0.65 (Equation 603.10.1)|
|Lmax||=||maximum permitted leakage, (ft3/min)/100
square feet [0.0001 (m3/s)/m2] duct surface
|CL||=||six, duct leakage class, (ft3/min)/100 square
feet [0.0001 (m3/s)/m2] duct surface area at
1 inch water column (0.2 kPa).
|P||=||test pressure, which shall be equal to the
design duct pressure class rating, inch
water column (kPa).
- Factory-installed plenums, casings, or ductwork furnished as a part of HVAC equipment tested and rated in accordance with approved energy efficiency standards.
- Ducts or plenums located in conditioned spaces where heat gain or heat loss will not increase energy use.
- For runouts less than 10 feet (3048 mm) in length to air terminals or air outlets, the rated R-value of insulation need not exceed R-3.5.
- Backs of air outlets and outlet plenums exposed to unconditioned or indirectly conditioned spaces with face areas exceeding 5 square feet (0.5 m2) need not exceed R-2; those 5 square feet (0.5 m2) or smaller need not be insulated.
- Ducts and plenums used exclusively for evaporative cooling systems.
Ductwork shall be connected to damper sleeves or assemblies in accordance with the fire damper manufacturer's installation instructions.
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:
- Smoke Damper
- Fire Damper
- Fire/Smoke Damper
- HVAC systems that are part of an engineered smoke evacuation system.
- Where the automatic activation causes all the smoke dampers and combination smoke-fire dampers to close in the enclosed space having a common atmosphere where openings are required to be protected.
- Where analysis demonstrates shutoff would create a greater hazard.
- Suspended ventilating ceiling material shall have a Class 1 flame spread classification on both sides, determined in accordance with the building code. Suspended ventilating ceiling supports shall be of noncombustible materials.
- Lighting fixtures recessed into ventilating ceilings shall be of a type approved for that purpose.
- Where the space supplied by the air-moving equipment is served by a total coverage smoke-detection system in accordance with the California Fire Code, interconnection to such system shall be permitted to be used to accomplish the required shutoff.
- Automatic shutoff is not required where occupied rooms served by the air-handling equipment have direct exit to the exterior, and the travel distance does not exceed 100 feet (30 480 mm).
- Automatic shutoff is not required for Group R, Division 3 and Group U Occupancies.
- Automatic shutoff is not required for approved smoke-control systems or where analysis demonstrates shutoff would create a greater hazard, such as shall be permitted to be encountered in air-moving equipment supplying specialized portions of Group H Occupancies. Such equipment shall be required to have smoke detection with remote indication and manual shutoff capability at an approved location.
- Smoke detectors that are factory installed in listed air-moving equipment shall be permitted to be used in lieu of smoke detectors installed in the main supply-air duct served by such equipment.