A post by Jeff Hugo, with National Fire Sprinkler Association
While most contractors, architects, and layout personnel are very savvy in the sprinkler standards, the IBC is not usually the first place they look for specific sprinkler requirements. This article and following articles are written for the AHJ to understand what is coming out of the IBC and when to apply this code language in their designs.
This first article we’ll take a look at Chapter 4 of the 2006 International Building Code. Chapter 4 covers additional requirements to certain uses and occupancies that are not addressed elsewhere. This brief summary of Chapter 4 covers what I believe is vital to the interest sprinkler requirements.
Covered malls are limited to three levels in height and no more than three stories above grade. Passive fire protection is not required between the tenant space and the mall, however a fire resistive wall is required between the tenant spaces. An anchor building – a building that is separate from the mall, but serves the mall, i.e. Kohl’s, Sears, etc – is required to have a fire wall at the attachment to the mall, unless the anchor building is the same use as the mall, then a 2-hour fire barrier is needed.
Fire sprinklers are required in all of the covered mall spaces. The sprinkler system must be installed throughout the entire structure, including occupied tenant spaces. Unoccupied tenant spaces are also required to have fire sprinklers operable unless alternative measures are in place and approved by the AHJ. Mall sprinkler systems must be separate from the tenant spaces and the anchor stores and have separate supervised control valves. Kiosks and children play structures that have roofs or overhead covers must also have sprinklers. While kiosks and play structures are constructed of approved non-combustible materials and foam plastics, they are limited to 300 sq. ft. in size.
Standpipes in covered malls are required where the floor of the topmost level is over 30 ft in height from the lowest level of fire department vehicle access or vice versa for levels underground. Even if covered malls fall under the 30 ft height requirement, Class I hose stations are required by the IBC. The location of the hose stations are: within the mall at the entrance to each exit passageway/corridor, at each floor-level landing within enclosed stairways opening directly on the mall and at the exterior public entrances to the mall. The most remote hose station must be sized to supply 250 gpm.
Fire sprinklers are required in high-rise buildings, (with a secondary water supply in Seismic Categories C,D,E, or F) except in open parking garages and telecommunication equipment buildings or spaces. A high-rise building also requires a fire command center, a special room or space separated by at least 1-hour fire barriers from the adjacent spaces. Along with several other requirements, fire sprinkler control valve supervision and water flow indicators must be displayed in the command center. Detailed fire sprinkler and standpipe drawings are also required inside the command center.
An atrium is a floor opening or a series of vertical floor openings that connect the environments of adjacent stories. Atriums and the adjacent floors connecting two or more stories shall be sprinkled. Sprinkler protection can be limited to only the atrium area if the atrium and adjacent floors are separated by 2-hour fire barrier. When the atrium and the adjacent building areas/floors are both protected by sprinklers then only a 1-hour fire barrier is needed.
The 1-hour fire barrier can be eliminated if a glass wall in a gasketed frame is installed. However, closely spaced sprinklers are required to cool the glass. When a walkway is on the atrium side of the glass wall, sprinklers are required to be spaced no more than 6 ft. apart, 4”-12” from the glass and be capable wetting the entire glass surface. If no walkway is present, then the sprinklers shall be installed in the same manner on the glass wall opposite of the atrium. Curtains, draperies, etc shall not obstruct the sprinklers and carefully note these obstructions with the architectural plans during the layout process.
The IBC also states that if the ceiling of the atrium is over 55 ft from the floor, then sprinkler protection at the ceiling is not required. Smoke control is required for all atriums three stories and more. Coordination with the mechanical contractor may be needed.
Use Group I-2 – Hospitals/Nursing Homes
This occupancy includes buildings and structures used for medical, surgical, psychiatric, nursing or custodial care on a 24-hour basis for more than five persons who are not capable of self-preservation. All I use groups are required to be sprinkled.
Quick response sprinklers are required for waiting areas and other similar areas open to the corridors. Patient rooms within smoke compartments shall be protected by quick response or residential sprinklers.
Use Group I-3 – Prisons/Jails
This occupancy includes buildings and structures that are inhabited by more than five persons who are under restraint or security and is occupied by persons who are generally incapable of self-preservation due to security measures not under the occupants’ control. All I use groups are required to be sprinkled.
Glazing in one exit enclosure (stairway) per building is permitted if protected on both sides by sprinklers capable of wetting both sides of the glazing simultaneously. The glazing shall be gasketed, similar to the atrium requirements, and sprinklers must not be obstructed.
A stage is a space within a building utilized for entertainment or presentations, which includes overhead hanging curtains, drops, scenery or stage effects other than lighting and sound. A stage differs from a platform, which is a raised area within a building used for worship, the presentation of music, plays or other entertainment; the raised area for lecturers; boxing and wrestling rings; and similar purposes wherein there are no overhead hanging curtains, drops, scenery or stage effects other than lighting and sound.
Stages shall be equipped with a sprinkler system. Sprinklers shall be installed under the roof and gridiron and under all catwalks and galleries over the stage. Sprinklers shall also be installed in dressing rooms, performer lounges, shops and storerooms accessory to such stages. Sprinklers are not required under stages less than 4 ft in height storing tables and chairs and are separated from other areas by 5/8” Type X drywall. Sprinklers are not required for stages 1,000 sq. ft. and less and are 50 ft or less in height that have curtains that cannot be retracted vertically. Portable orchestra enclosure on stages are also not required to be sprinkled.
Standpipes shall be installed on each side of the sprinkled stage greater than 1,000 sq. ft. Hose connections for sprinkled stages shall be a minimum of 1 ½” according to NFPA 13 or NFPA 14 for Class II or Class III standpipes. The hose cabinet shall provide lengths to cover the stage area and shall be equipped with approved fog nozzles.
Aircraft hangars and aircraft paint hangars shall be provided with fire suppression as required by NFPA 409, except that Group II hangars defined by NFPA 409 storing private aircraft without major maintenance or overhaul are exempt from foam suppression systems.
High Hazard Use Groups – H-1 through H-5
High Hazard use groups are classified from H-1 through H-5. These uses include buildings or structures that involve manufacturing, processing, generation, or storage of material in certain quantities that constitute a physical or health hazard. All H use groups are required to be sprinkled.
The installation of HPM (Hazardous Production Materials) piping and tubing within the space defined by the walls of corridors and the floor or roof above, or in concealed spaces above other occupancies are required to have sprinklers in these spaces unless the space is 6” or less in the smallest dimension.
A sprinkler system shall be provided in the following exhaust ducts conveying gases, vapors, fumes, mists or dusts generated from HPM:
- Sprinklers shall be provided in metallic and noncombustible nonmetallic exhaust ducts where the largest cross-sectional diameter is equal to or greater than 10 inches, the ducts are within the building and the ducts are conveying flammable gases, vapors or fumes.
- Sprinklers shall be provided in combustible nonmetallic exhaust ducts where the largest cross-sectional diameter of the duct is equal to or greater than 10 inches, unless, ducts are approved for applications without a sprinkler system, and ducts are 12 ft. or less and installed below the ceiling
- Sprinklers shall be installed at 12-foot intervals in horizontal ducts and at changes in direction. In vertical ducts, sprinklers shall be installed at the top and at alternate floor levels.
This article captures many of the additional code requirments for automatic sprinklers beyond those outlined in Section 903 of the International Building and Fire Codes. Future articles will look at adding to these requirements and providing additional resources as to when sprinkler systems are required.