FIRE PROTECTION SYSTEMS

Section 901 General

Section 903 Automatic Sprinkler Systems

Section 904 Alternative Automatic Fire-Extinguishing Systems

Section 905 Standpipe Systems

Section 907 Fire Alarm and Detection Systems

Section 909 Smoke-Control Systems

Section 910 Smoke and Heat Removal

Section 911 Fire Command Center

Section 914 Emergency Responder Safety Features

Key Points

Section 901 General

It is the intent of this chapter to require fire protection systems in those buildings and with those uses that through experience have been shown to present hazards requiring the additional protection provided by fire protection systems. The installation, repair, operation, and maintenance of such systems are based on the provisions of the IBC and the International Fire Code® (IFC®). Furthermore, it is the intent of the code to prescribe standards for those systems that are required. However, there are times when the installation of a fire-protection system is not based on a code mandate. In such situations, the nonrequired system must still meet the provisions of the code. Once fire protection is provided to some degree, it is expected that the system is properly installed.

An exception to this section permits a fire protection system or any portion of that system that is not required by the code to be installed for partial or complete protection, provided that the installation meets the code requirements. As an example, fire-sprinkler protection may be provided only in a specific area of a building, based on a request by the owner rather than on a requirement of the code. Although the sprinkler system must be installed in accordance with the proper design standard (in most cases NFPA 13), it is not necessary that the sprinkler system extend into other areas of the building.

More than likely, however, a fire protection system is used to gain exceptions to, or reductions in, other code requirements. Under these conditions, the fire protection system is considered a required system and is subject to all of the requirements imposed by the IBC and IFC.

901.7   Fire areas.   The fire area concept is based on a time-tested approach to limiting the spread of fire in a building. Through the use of fire-resistive elements, compartments can be created that are intended to contain a fire for a prescribed period of time. The floor area that occurs within each such compartment is considered to be the fire area. By definition, a fire area is the aggregate floor area enclosed and bounded by fire walls, fire barriers, exterior walls, and/or fire-resistance horizontal assemblies of a building. See Figure 901-1. In addition, any areas beyond the exterior wall that are covered with a floor or roof above, such as a canopy extending from the building, are considered part of the building for fire area purposes. This approach is consistent with the determination of building area in Chapter 2. An example is shown in Application Example 901-1. By isolating a fire condition to a single fire area through the use of fire separation elements, only a portion of the building is considered at risk because of a single fire incident.

Figure 901-1   Fire areas.

The use of fire areas as a fire protection tool is limited almost exclusively to the requirements for automatic sprinkler systems. Other fire protection systems, such as fire alarm systems, are for the most part regulated by methods that are not based on the fire area concept. Even within the automatic sprinkler provisions of Section 903.2, only a portion of the requirements use the fire area approach as an alternative means of protection. The fire area methodology set forth in the IBC, applicable only in limited occupancy groups under limited conditions, allows for the omission of automatic sprinkler protection.

Application Example 901-1

As an example, the provisions of Section 903.2.3, Item 1 require that a fire area containing a Group E occupancy that exceeds 12,000 square feet (1,115 m²) in floor area be provided with an automatic sprinkler system. Conversely, where the fire area size does not exceed the established threshold of 12,000 square feet (1,115 m²), a sprinkler system is not required unless mandated by another code provision. Where the building under consideration is limited to a maximum of 12,000 square feet (1,115 m²), it can be viewed as a single fire area, and no sprinkler system is mandated. However, where the building exceeds 12,000 square feet (1,115 m²) in floor area, two or more fire areas must be established to eliminate the sprinkler requirement. Table 707.3.10 is referenced because it sets forth the minimum required level of fire resistance necessary to create an adequate fire separation between the fire areas that are established. In the example, and assuming the Group E building is 20,000 square feet (1,858 m²) in total floor area, at least two fire areas must be created as an alternative to sprinkler protection. Neither of the two fire areas is allowed to exceed 12,000 square feet (1,115 m²), and Table 707.3.10 indicates that the minimum fire separation between the two fire areas must be 2 hours. Therefore, a minimum 2-hour fire-resistance-rated fire wall, fire barrier, or horizontal assembly, or a combination of these elements, would be required.

A similar approach is taken in a mixed-occupancy building where the multiple fire areas are of different occupancy classifications. The minimum required fire-resistance rating for the separation between the fire areas would also be based on the requirements of Table 707.3.10. For example, where a building contains a 10,000-square-foot (929-m²) Group M occupancy and a 6,000-square-foot (558-m²) Group F-1 occupancy, the minimum fire-resistive separation between the Group M fire area and the Group F-1 fire area would be 3 hours. Although the Group M requirement in Table 707.3.10 only mandates a 2-hour separation, a minimum 3-hour fire separation is required for a Group F-1 occupancy. For further information, see Application Example 901-2 and the discussion of Table 707.3.10.

Application Example 901-2

Section 903 Automatic Sprinkler Systems

In general, automatic sprinkler systems are required when certain special features and hazards of specific buildings, areas, and occupancies are such that the additional protection provided by sprinkler systems is warranted.

In addition, there occasionally are inadequate numbers and sizes of openings in the exterior walls from which a fire may be fought from the exterior of the building. The provisions requiring sprinklers in these so-called windowless buildings apply to all buildings, regardless of occupancy, except for Group R-3 and U occupancies.

There are three general situations in which sprinkler or other fire suppression systems are to be provided within a building. An automatic sprinkler may be required throughout the building, throughout a fire area, or only in the specific room or space where sprinkler protection is necessary. Examples are depicted in Figure 903-1.

Figure 903-1   Sprinkler requirements.

1.   Throughout the building. There are numerous applications of the code that require the entire building to be sprinklered, either mandated because of a code requirement or used as a substitute for other fire- and life-safety features. Examples include the requirement for sprinklers throughout all buildings containing a Group I fire area per Section 903.2.6 and the elimination of corridor fire protection in some occupancies based on Table 1020.1, note c. The extent of required sprinkler protection in Group A occupancies is described in a different manner, but quite often results in a fully sprinklered condition. Initially, only the specific Group A occupancy must be provided with sprinklered protection where exceeding the limits established by Sections 903.2.1.1 through 903.2.1.4. However, as mandated by Section 903.2.1, the sprinkler system must also be provided throughout the story where the Group A occupancy is located. In addition, all floor levels between the Group A occupancy and the level of exit discharge must be sprinklered. This will commonly result in a requirement that the entire building be provided with an automatic sprinkler system. Additional commentary is provided in the discussion of Section 903.2.1.

2.   Throughout a fire area. In Section 903.2, a variety of provisions require only those fire areas that exceed a certain size or occupant load, or are located in a specific portion of the structure to be sprinklered. The sprinkler requirements based on fire area include the provisions of Section 903.2.3 for Group E occupancies and Section 903.2.4.1 for woodworking operations.

A variation of this requirement occurs in those mixed-occupancy buildings containing a Group H-2, H-3, or H-4 occupancy. The code only mandates that the sprinkler system be provided in the Group H portion, not the entire building. However, since all other occupancies in a mixed-occupancy building must be appropriately isolated from the Group H occupancy because of the separated occupancies provisions of Section 508.4, the result is basically a requirement to sprinkler the Group H compartment.

3.   Specific rooms or areas. Occasionally, only a specific portion of the building requires the protection provided by a sprinkler system. The sprinkler addresses the particular hazard that occurs at possibly only a single location. For example, the allowance for a reduction in the flame-spread classification of interior finishes from Table 803.11 is based on sprinkler protection in the room, area, or exitway where the finish under consideration is installed.

903.1.1   Alternative protection.   Where an automatic sprinkler system is addressed in the IBC, alternative automatic fire-extinguishing systems are acceptable, provided they are installed in accordance with approved standards. These systems, regulated by Section 904, include special systems required by the IFC and other types of systems such as dry chemical, carbon dioxide, or aqueous-foam systems. This is one of the few provisions in the IBC where approval must come from someone other than the building official. Although the building official is almost always charged with making any decisions regarding the building code, the fire code official is typically better able to evaluate and determine the appropriateness of an alternative fire-extinguishing system. It is important to note that where an automatic sprinkler system is recognized by the code for the purpose of an exception or reduction to a requirement, the use of an alternative fire-extinguishing system will not provide such a benefit. See Section 904.2.1.

903.2   Where required.   It is the intent of this section to specify those occupancies and locations where automatic sprinkler systems are required. A fire-extinguishing system is a system that discharges an approved fire-extinguishing agent such as water, dry chemicals, aqueous foams, or carbon dioxide onto or in the area of a fire. A fire sprinkler system discharges water only. The code specifies a fire sprinkler system in this section, as it is the intent of the code that water be applied and not one of the other extinguishing agents. Generally, water is the most effective extinguishing agent for fires. Only where water creates problems, such as in magnesium or calcium carbide storage areas, would some other type of extinguishing agent be required. The allowance for the installation of a system other than an automatic sprinkler system is subject to approval by the fire code official. Section 904.2.1 states that where an automatic fire-extinguishing system is installed as an alternative to the required automatic sprinkler system of Section 903, it cannot be used for the purposes of exceptions or reductions allowed by other code provisions. Alternative automatic fire-extinguishing systems are addressed in Section 904.

Fire areas. Most of the requirements of this section are based on the concept of fire areas. Where a fire area exceeds a specified size, is located in a certain portion of the building, or exceeds a specified occupant load, the code often requires the installation of an automatic sprinkler system to address the increased hazards and concerns that exist. The provisions for fire areas can be found in various sections of the IBC.

The definition of “fire area” is located in Chapter 2. A fire area is “the aggregate floor area enclosed and bounded by fire walls, fire barriers, exterior walls or fire-resistance-rated horizontal assemblies of a building.” Complete isolation and separation of a portion of a building from all other interior areas is provided for a fire area through the use of fire-resistance-rated construction and opening protectives. The total floor area within the enclosed area, including the floor area of any mezzanines or basements, is considered the size of the fire area. See Application Example 903-1. It is also important to note that “areas of the building not provided with surrounding walls shall be included in the fire area if such areas are included within the horizontal projections of the roof or floor next above.”

Application Example 903-1

Where fire walls are used, Section 503.1 indicates that each portion of the structure included within the fire walls is considered a separate building. This concept would be consistent with that of separate and distinct fire areas being created through the use of fire walls. The fire-resistance rating of the wall and the fire-protective ratings of any openings in the fire wall are identified in Chapter 7. Also see the discussion of Section 706.1 where the fire wall separates different occupancies.

Fire barriers and fire-resistance-rated horizontal assemblies may also be used to create fire areas, provided the fire-resistance-rated construction totally separates one interior area from another. In order to determine the minimum fire-resistance rating of the vertical and horizontal elements, the occupancy classifications of the areas being separated must be identified. Table 707.3.10 is then referenced to determine the minimum fire-resistance rating of the separation. The use of this table is applicable to both single-occupancy and mixed-occupancy buildings, as illustrated in Application Example 903-2. Where the fire area separation occurs between two fire areas of the same occupancy, the hourly rating established by Table 707.3.10 for that single occupancy classification is applied. If the fire areas are of different occupancy classifications, the controlling fire-resistance rating of the fire barrier or horizontal assembly separating the occupancies is based on the higher of the ratings as established by Table 707.3.10 for the occupancies involved. For further information, see the discussions of Section 901.7 and Table 707.3.10.

Application Example 903-2

Because the majority of sprinkler provisions are based on the size of the fire area, it is sometimes possible for the designer to eliminate the requirement for sprinklers by reducing the floor area within the surrounding fire-resistance-rated construction. The use of fire walls or fire barriers and fire-resistance-rated horizontal assemblies can subdivide a structure into smaller, less hazardous areas that are of such a size that sprinklers are not necessary. See Application Example 903-3. This concept of compartmentation has been used in building codes for decades as an effective method of reducing the loss of life and property in fires.

The exception to Section 903.2 eliminates the sprinkler requirement in telecommunications occupancies in those rooms or areas dedicated solely for essential telecommunications and power equipment. The alternative protection is provided through the required installation of an automatic fire alarm system, as well as fire-resistance-rated separation from other areas of the building.

903.2.1   Group A.   Because of the potentially high occupant load and density anticipated in Group A occupancies, coupled with the occupants’ probable lack of familiarity with the means of egress system, various assembly uses must be protected by an automatic sprinkler system. Where an automatic sprinkler system is required for a Group A occupancy, the system must be installed throughout the entire story where the Group A occupancy is located. In addition, where the Group A occupancy requiring a sprinkler system is located on a floor level other than the level of exit discharge, all floor levels between the Group A occupancy and the nearest level of exit discharge must be sprinklered as well. By expanding the areas of the building required to be protected by an automatic sprinkler system beyond just the assembly areas, the code provides for protection adjacent to the Group A areas as well as throughout the means of egress. Figures 903-2 and 903-3 illustrate these fundamental provisions.

Figure 903-2   Group A sprinkler.

Figure 903-3   Group A fire area.

Application Example 903-3

903.2.1.1   Group A-1.   The combination of highly concentrated occupant loads, high numbers of occupants, reduced lighting levels, and potentially high fuel loads create a level of hazard that justifies the need for sprinkler protection. Therefore, fire areas containing theaters and similar assembly uses intended for the viewing of motion pictures or the performing arts shall be provided with an automatic sprinkler system where any one of the following conditions exists:

1.   The fire area containing the Group A-1 occupancy exceeds 12,000 square feet (1,115 m²).

2.   The occupant load of the fire area exceeds 299.

3.   The fire area is located on any floor level other than that of the exit discharge.

It should also be noted that any fire area containing a multitheater complex, defined as two or more theaters served by a common lobby, shall be provided with a sprinkler system throughout the fire area.

903.2.1.2   Group A-2.   Fire areas housing uses intended for food or drink consumption are regulated for sprinkler protection at a higher level than other enclosed assembly occupancies. Even where the occupant load is not excessive, the hazards associated with such uses warrant the protection provided by a sprinkler system. Oftentimes, the consumption of alcohol beverages by the building’s occupants creates an environment more likely to be unsafe. The reduced lighting levels in some uses, along with the probability of loose chairs and tables, also increase the risk for obstructed egress. The record of casualties during fires in buildings housing nightclubs, casino gaming areas, restaurants, and similar types of uses demonstrates the need for the additional protection provided by fire sprinklers or, alternatively, the separation of the use into smaller compartments. The code intends that fire areas exceeding 5,000 square feet (465 m²) that contain Group A-2 uses be provided with an automatic sprinkler system, as well as such uses having an aggregate occupant load within the fire area of 100 or more, or where the fire area is located on a floor level other than the level of exit discharge.

903.2.1.3   Group A-3.   The sprinkler threshold for a Group A-3 occupancy is identical to that for a Group A-1 occupancy. As such, where any fire area in a Group A-3 occupancy exceeds 12,000 square feet (1,115 m²), where the fire area has an occupant load greater than 299 or where the assembly occupancy is located on any floor other than the exit discharge level, an automatic sprinkler system is required. In applying the provisions of this section, it is important to note that the occupant load threshold is based on the number of people within the entire fire area, not just in each assembly room. See Application Example 903-4.

The code requirements for these types of uses, specifically for exhibition and display rooms, can be strongly attributed to the McCormick Place fire in Chicago on January 16, 1967. McCormick Place was not sprinklered and consisted of three levels, including a main exhibit area of 320,000 square feet (29,728 m²) on the upper level. Both the upper and lower levels were in the final stages of readiness for a housewares exhibition and were heavily laden with combustibles when the fire broke out. The fire was reported to have originated in the storage area behind an exhibit booth on the upper level. The upper level was almost totally destroyed, and considerable damage occurred to the lower level.

Application Example 903-4

Ordinarily, assembly occupancies are considered to have a very low fire loading; however, the need for built-in fire suppression for an assembly use that is used for exhibition or display purposes was clearly demonstrated by the McCormick Place fire. Display booths are most often constructed with combustible materials, and the storage area behind the booths is a receptacle for combustible materials and packing boxes. Thus, without built-in fire suppression, the large quantities of combustible materials and large areas combine to create an excessive hazard. Many other assembly occupancies classified as Group A-3 also present significant fire loading such as art galleries, libraries, and museums. Therefore, sprinkler protection is beneficial for all large Group A-3 occupancies.

903.2.1.4   Group A-4.   The fire-sprinkler requirements for Group A-4 occupancies (those assembly uses provided with spectator seating for the viewing of indoor activities and sporting events) are identical to the provisions for Group A-1 and A-3 uses. See Section 903.2.1.3 for a discussion of the sprinkler requirements.

903.2.1.5   Group A-5.   The fire loading in stadiums and grandstands is typically quite low except for specific accessory areas such as concession stands, storage and equipment rooms, press boxes, and ticket offices. Therefore, assembly occupancies classified as Group A-5 do not require the installation of an automatic sprinkler system except for those support areas exceeding 1,000 square feet (92.9 m²) in floor area. The limitation of 1,000 square feet (92.9 m²) is based on the floor area of each individual area and not on the aggregate area of all such spaces. Where such accessory spaces are of a considerable size, the hazards posed by the potentially large quantities of combustible materials can be reduced where such areas are sprinklered.

903.2.1.6   Assembly occupancies on roofs.   Where a large Group A occupancy is located on the roof of a building other than a parking garage of noncombustible construction, all floor levels below the occupied roof must be sprinklered as illustrated in Figure 903-4. The sprinkler protection shall extend to, and include, the level of exit discharge. Whether building occupants are located on an upper story or on the roof, they are exposed to a similar hazard as they travel down through the building to the discharge level. It should be noted that this provision does not require the roof to be sprinklered or provided with any alternative fire-extinguishing system.

Figure 903-4

The application of this provision should not be extended to other areas of the code. For example, the occupied roof is not considered as building area, fire area, or a story. Therefore, even though an occupied roof is viewed as being an assembly occupancy, the limitations of Table 504.4 and many other code provisions would not apply.

903.2.1.7   Multiple fire areas.   The option of compartmentalizing Group A occupancies into separate fire areas simply to avoid any sprinkler requirement is limited in its application. Where the fire areas share a common egress system and the combined occupant load of the Group A fire areas exceeds an occupant load of 299, sprinkler protection is required in accordance with Section 903.2.1.

Figure 903-5 depicts a condition where a sprinkler system is required even though multiple complying fire areas have been provided. An occupant load of 360 must be assigned to the corridor based upon the full contributing occupant loads of the Group A occupancies. Note that for purposes of this provision, 100 percent of the occupant loads of the Group A-1 and A-2 spaces must be assigned to the corridor because partial occupant loads are not to be considered.

Figure 903-5   Sprinklered Group F-1 occupancies.

903.2.2   Ambulatory care facilities.   As a general rule, Group B occupancies do not require a sprinkler system based solely on their occupancy classification. However, Section 903.2.2 mandates that a Group B ambulatory care facility be provided with an automatic sprinkler system when either of the following conditions exists at any time:

•   Four or more care recipients are incapable of self-preservation, or

•   One or more care recipients who are incapable of self-preservation are located at other than the level of exit discharge.

Although such facilities are generally regarded as moderate in hazard level due to their office-like conditions, additional hazards are typically created due to the presence of individuals who are temporarily rendered incapable of self-preservation due to the application of nerve blocks, sedation, or anesthesia. While the occupants may walk in and walk out the same day with a quick recovery time after surgery, there is a period of time where a potentially large number of people could require physical assistance in case of an emergency that would require evacuation or relocation. The installation of an automatic sprinkler provides an important safeguard that enables the moderate-hazard classification of Group B.

The sprinkler system, when required, must extend throughout the entire story on which the ambulatory care facility is located. In addition, in multistory buildings where ambulatory care is provided above and/or below the exit discharge level, the sprinkler system must be installed on those stories between the level of ambulatory care and the level of exit discharge, inclusive.

903.2.3   Group E.   History has shown that educational occupancies perform quite well when it comes to fire- and life-safety concerns. Much of this can be attributed to the continuous control and supervision that takes place within schools, as well as the students’ knowledge of egress responsibilities in case of a fire or other emergency. However, because of the potential for moderate to high combustible loading, fire areas in Group E occupancies that exceed 12,000 square feet (1,115 m²) in floor area must be provided with an automatic sprinkler system. In addition, fire sprinklers are required for those portions of educational buildings located below the lowest level of exit discharge regardless of floor area.

903.2.4   Group F-1.   Without an automatic sprinkler system to limit the size of a fire, the fire can spread very quickly to other portions of the structure. This is particularly true for large floor-area buildings containing combustible materials such as manufacturing facilities, warehouses, and retail sales buildings. The IBC requires an automatic sprinkler system to be installed throughout any building containing a Group F-1 occupancy where the fire area containing the Group F-1 exceeds 12,000 square feet (1,115 m²). A fire sprinkler is also required where the building housing the Group F-1 occupancy is four stories or more in height or has an aggregate of Group F-1 fire areas in the building of more than 24,000 square feet (2,230 m²). The aggregate Group F-1 fire area would also include the floor area of any mezzanines involved. The 24,000-square-foot (2,230-m²) limitation would also be applicable in both single-story and multistory structures.

The potential for increased fire loading in a Group F-1 occupancy where upholstered furniture or mattresses are manufactured causes the threshold for automatic sprinkler protection to be reduced well below the general requirement. The sprinkler mandate is based on only that floor area of the facility devoted to the manufacture of upholstered furniture or mattresses, rather than the size of the entire fire area in which the manufacturing process occurs. The 2,500-square-foot (232-m²) threshold, although arbitrary in nature, represents a reasonable top-end limit where sprinkler protection is not required. It is also consistent with the sprinkler requirements of IFC Table 3206.2 addressing high-piled combustible storage of high-hazard commodities in buildings not typically accessible to the public. The code is unclear as to the appropriate method for determining the boundaries of the area used for the manufacture of upholstered furniture or mattresses. It would seem appropriate that all such manufacturing areas that could be quickly involved in a fire event originating at a single location be used in applying the code provision. Those manufacturing areas with adequate spatial or fire-resistive separation could possibly be excluded in the aggregate floor area determination. It is incumbent upon the authority having jurisdiction to apply the sprinkler requirement in a manner that reflects its intent based on the potential hazard that could be created in the manufacturing process.

903.2.4.1   Woodworking operations.   Because of the special hazards involving dusts created during woodworking operations such as sanding and sawing, this section requires that an automatic fire-sprinkler system be installed in fire areas of Group F-1 woodworking occupancies where the floor area of such operations exceeds 2,500 square feet (232 m²). Where equipment, machinery, or appliances that generate finely divided combustible waste or that use finely divided combustible materials are a portion of a woodworking operation, the size of the operation is strictly limited unless sprinklers are installed. An example of this provision is shown in Figure 903-6. The provision is based on the size of the area where only the sanding, sawing, and similar operations occur, not necessarily the floor area of the entire woodworking operation. However, because these types of operations occur quite often as an integral part of the overall woodworking activities, rather than isolated in their own room or area, some means of regulating and controlling the hazard should be provided.

Figure 903-6   Woodworking operations.

903.2.5   Group H occupancies.   Group H occupancies are high-hazard uses, and one special feature is that, in addition to presenting a local hazard within the building, it has a potential for presenting a high level of hazard to the surrounding properties. Therefore, the code requires sprinkler protection for all Group H occupancies. Note that the sprinkler system is not necessarily required throughout the entire building that contains a Group H-2, H-3, or H-4 occupancy. Only such Group H areas must be provided with a sprinkler system. In the case of a Group H-1 occupancy, no other occupancies are permitted in the same building. Therefore, a building housing a Group H-1 occupancy must be sprinklered throughout. In addition, buildings containing Group H-5 occupancies require sprinklers in other portions of the building as well as in the high-hazard area proper. This requirement is based on the original premise that the primary protection feature of this highly protected use is the automatic sprinkler system. For the purpose of sprinkler-system design, all areas of a Group H-5 are considered Ordinary Hazard Group 2, except for storage rooms with dispensing operations, which are considered Extra Hazard Group 2.

903.2.6   Group I.   Because the mobility of the occupants of Group I occupancies is greatly diminished (in the case of hospitals and detention facilities, the self-mobility is essentially nonexistent), the code requires an NFPA 13 automatic sprinkler system throughout any building where a Group I fire area exists. For supervised residential facilities classified as Group I-1, Condition 1 occupancies, allowances are made for the use of an approved NFPA 13R system. The similarities between this Group I use and those uses classified as Group R justify the reduction in sprinkler protection.

Exception 2 provides the only instance in which a building containing a Group I occupancy is not required to be provided with some type of automatic sprinkler system. Day-care facilities classified as Group I-4 occupancies are not required to be sprinklered where the day-care operations only occur at the level of exit discharge and every room where care is provided has an exit door that leads directly to the exterior. This allowance is similar in some respects to the allowance in Section 308.6.1 where day-care operations consistent with a Group I-4 classification may be classified as a Group E occupancy.

903.2.7   Group M.   The typical American supermarket evolved during the construction boom that followed World War II. At that time, the typical supermarket consisted of a one-story building of moderately large area, e.g., 15,000 to 25,000 square feet (1,394 to 2,323 m²). During the 1950s, fire statistics indicated that large-area supermarkets without sprinkler protection were subject to a larger proportion of fires than were usually attributable to this use in the past. As a result, building codes began requiring sprinklers in larger retail sales occupancies. The present requirements, detailed in the discussion in Section 903.2.4, are based on any of three factors: the size of the fire area, the number of stories, or the combined fire area on all floors. In addition, reference to the IFC is made for sprinkler protection in mercantile buildings where merchandise is placed in high-piled or rack storage. The installation of an automatic sprinkler system is also mandated in any Group M occupancy that is used for the display and sale of upholstered furniture or mattresses where the floor area devoted to such goods exceeds 5,000 square feet (464 m²). This provision is not based on the size of the fire area of the Group M occupancy—instead, it is based on the amount of floor area devoted to the specific contents of the mercantile occupancy. The requirement does not apply to the display and sale of furniture that is not upholstered, such as furniture constructed entirely of wood, plastic, or metal. Similar provisions are established for Group F-1 and S-1 occupancies where upholstered furniture or mattresses are manufactured or stored, respectively. See the discussion of Section 903.2.4 for further commentary. The increased threshold for sprinkler protection in Group M occupancies is based in part on an anticipated lower density of goods within a display area.

903.2.8   Group R.   In hotels, apartment buildings, dormitories, and other Group R occupancies, occupants may be asleep at the time of a fire, and may experience delay and disorientation in trying to reach safety. In addition, fire hazards in residential uses are often unknown to most occupants of the building, as they are created within an individual dwelling unit or guestroom. This helps to explain why these occupancies have a poor fire record when it comes to injury and loss of life. Therefore, an automatic sprinkler system is required throughout any building containing a Group R occupancy. The sprinkler requirement applies to the entire building and not just the fire area containing the Group R occupancy.

903.2.9   Group S-1.   In a manner consistent with that for Group F-1 and M occupancies, buildings containing combustible storage and warehousing uses must be provided with an automatic sprinkler system where the floor area or height exceeds the specified threshold. The sprinkler requirement is based on the probable presence of large amounts of combustible materials, typically arranged in a highly concentrated manner.

Although the storage of commercial trucks, buses, and similar motor vehicles is typically regulated under the provisions of Section 903.2.10.1, there are situations where the parking of such vehicles occurs in the same area with other Group S-1 uses. Therefore, these multipurpose spaces, such as fire station bays, are more appropriately classified as Group S-1 occupancies. In such cases, a more restrictive threshold of 5,000 square feet (464 m²) is used to require sprinkler protection.

The storage of upholstered furniture and mattresses poses much the same hazard as in buildings where such goods are manufactured or displayed. Therefore, the sprinkler requirements are to a great degree consistent with those for Group F-1 and M occupancies where upholstered furniture or mattresses are present. Additional information is provided in the commentary on Sections 903.2.4 and 903.2.7.

903.2.9.1   Repair garages.   The unique hazards associated with vehicle repair garages may be addressed in part through the installation of an automatic sprinkler system. However, the requirement for sprinklers is limited only to those repair garages that present a high level of concern based on size or location. By locating the repair garage above grade in a building of one or two stories, the size of the fire area containing the garage becomes the controlling factor in the determination of whether or not a sprinkler system is required. Where there is vehicle parking in the basement of a building used for vehicle repair, the building must be sprinklered regardless of fire area size. The sprinkler requirement is applicable even where the repair activity occurs only above the basement level. In buildings where commercial motor vehicles are repaired, the threshold for sprinkler protection is consistent with that established in Section 903.2.10.1 for commercial parking garages.

903.2.10   Group S-2 enclosed parking garages.   Because the bulk of the uses designated as Group S-2 occupancies present very low fire-load potential, there is generally no requirement for these low-hazard occupancies to be sprinklered. However, where the Group S-2 portion of a building is an enclosed parking garage, the hazard level is increased. There is a need to protect other uses housed above an enclosed parking garage; thus, a Group S-2 enclosed parking garage is required to be sprinklered where the garage is located below another occupancy. In fact, in such a situation the entire building must be sprinklered, regardless of the size of the garage itself. There is an exception to the sprinkler requirement where an enclosed parking garage is located beneath a Group R-3 occupancy. Where the enclosed parking garage has no uses above, the required point at which an automatic sprinkler system is required is consistent with the threshold established for other moderate-hazard occupancies. The installation of an automatic fire sprinkler system for enclosed parking garages is required where the fire area containing the garage exceeds 12,000 square feet (1,115 m²) in floor area. The fire behavior in an enclosed parking garage, although similar to that in an open parking garage, is of greater concern since smoke ventilation will be more difficult due to the lack of sufficient exterior openings. This concern is addressed by the required installation of an automatic sprinkler system once the 12,000-square-foot (1,115-m²) fire area threshold is exceeded. The sprinkler requirement is not applicable to open parking garages.

903.2.10.1   Commercial parking garages.   Where the vehicles stored within a building consist of commercial trucks and buses, the code mandates stringent floor areas when it comes to the requirement for an automatic sprinkler system. Where a fire area containing commercial parking exceeds 5,000 square feet (464 m²) in floor area, the building housing the vehicles must be sprinklered throughout. The provision is intended to address those facilities housing larger vehicles. It is generally not applicable where pick-up trucks and similar-sized vehicles are being used for business activities.

903.2.11.1   Stories without openings.   The provisions of this section make specific the intent of the code to require automatic sprinkler protection in windowless buildings. A structure having inadequate openings on the exterior wall as determined by this section such that fire department access is insufficient is considered a windowless building. The requirements of this section apply to all occupancies except Groups R-3 and U. The provisions are applicable on a floor-by-floor basis and do not apply to any story above grade plane or basement having a floor area of 1,500 square feet (139.4 m²) or less:

•   On the basis of each individual story above ground.   Each individual story is analyzed for the size and the number of exterior wall openings. Thus, in a multistory building, it is possible to have a requirement that a sprinkler system be installed in one story and not in another.

The code requires that the openings be:

1.   Installed entirely above the adjoining ground level.   This provision is necessary so that effective fire suppression and rescue can be accomplished from the exterior of the building.

Where the openings cannot be located entirely above the adjoining ground level, the code permits the use of exterior stairways or ramps that lead directly to grade.

2.   Of adequate size and spacing.   Although it may be argued that the openings required by the code are not the equivalent of automatic fire-sprinkler protection, the access for fire fighting provided by the openings has proven satisfactory.

Although not expressly stated in the code, there is an expectation that a below-grade opening used to satisfy this provision be simply a typical 3-foot by 6-foot, 8-inch (914-mm by 2032-mm) door leading directly to the exterior stairway or ramp. However, above-grade openings are more specifically addressed. A total of 20 square feet (1.86 m²) of openings is mandated in each 50 lineal feet (15,240 mm) of exterior wall. It is not necessary to obtain all 20 square feet (1.86 m²) from a single opening, as long as the minimum dimension requirement of 30 inches (762 mm) is met. Multiple 30-inch by 30-inch (762-mm by 762-mm) openings would comply; however, they may not be as effective as a larger single opening.

The intent of the code is that there shall be at least one opening in each 50 linear feet (15,240 mm) of exterior wall. It may be better stated that any wall section of 50 feet in length be provided with complying openings. Thus, an exterior wall 100-feet (30,480-mm) long with 20-square-foot (1.86-m²) openings located at third points along the wall would comply, as shown in Figure 903-7. There is no portion of the wall that is 50 feet (15,240 mm) in length that does not contain the necessary openings. However, the same wall with such openings located at each end, as depicted in Figure 903-8, will not comply with the intent of the code insofar as there is a length of wall that exceeds the 50-foot (15,240-mm) dimension without an opening. Certainly, the same wall with only one 40-square-foot (3.72-m²) opening at one end also would not comply.

Figure 903-7   Required exterior openings.

Figure 903-8   Required exterior openings.

3.   Accessible to the fire department from the exterior.    Surely, the openings would be of no value for fire fighting if the fire-fighting forces could not gain access. The mere fact that the openings may be 30 or 40 feet (9,144 or 12,192 mm) above grade does not mean the openings are inaccessible. However, if, with the resources available to the fire department, access cannot be obtained to the openings, they would be considered inaccessible. The determination of accessibility rests with the building official. However, personnel in a fire department should be consulted for their professional opinions and also for their knowledge of the capabilities of their equipment.

4.   Adequate to allow access for fire fighting to all portions of the interior of the building. For this reason, the code requires that where openings are provided on only one side and the opposite exterior wall is more than 75 feet (22,860 mm) away, sprinklers shall be provided, or, as an alternative, openings shall be provided on at least two sides. The 75-foot (22,860-mm) distance is a straight-line measurement taken between the two opposing walls. Where complying openings are required in two exterior walls because of the 75-foot (22,860-mm) limitation, the openings are permitted on either two adjacent sides or opposite sides on the assumption that, with two exterior sides having openings, adequate access may be gained to effectively fight the fire.

In other than basements, the provisions requiring openings in exterior walls do not extend beyond the exterior wall line into the building. Thus, the code does not typically dictate specific openings for interior partition arrangements, because the normal openings provided through interior partitions provide adequate accessibility to all interior portions of the building.

5.   Applicability. As previously noted, the provisions of Section 903.2.11.1 apply to every story, including basements, of all buildings where the floor area exceeds 1,500 square feet (139.4 m²). Figures 903-9 and 903-10 provide additional graphic representations of the requirements of this section. Basements are considered to be somewhat more difficult than stories above grade when it comes to fighting fires from the exterior of the building. Therefore, an additional requirement is imposed in addition to those of Section 903.2.11.1.2. The code provides that when any portion of a basement is located more than 75 feet (22,860 mm) from complying exterior wall openings, the basement is required to be provided with an automatic sprinkler system. The 75-foot (22,860-mm) measurement should be taken in a straight line, resulting in the use of the arc method, as shown in Figure 903-11. The two methods of providing complying exterior openings set forth in Section 903.2.11.1 are both available for a basement condition. If the openings are available entirely above the adjoining ground level, they are regulated in the same manner as for floor levels above grade. Otherwise, the openings must lead directly to a complying exterior stairway or ramp. The 75-foot (22,860-mm) criterion is only applicable where the basement is a wide-open space with no interior walls or partitions that could obstruct a fire-hose water stream. Where the basement contains such walls or partitions, a sprinkler system is always required in the basement if it exceeds 1,500 square feet (139.4 m²) in floor area.

Figure 903-9   Maximum distance between walls.

Figure 903-10   Access to required openings.

Figure 903-11   Openings in basement.

With regard to the allowance that the exterior wall openings may be located below grade, areaways and light wells are considered to meet this requirement. However, the light wells and areaways should be provided with a stairway or ramp for gaining ready access to the openings. Furthermore, the plan dimensions of the areaway or light well should be adequate to permit the necessary maneuvering to accomplish fire fighting or rescue from the opening. On this basis, it is advisable to consult with the fire department personnel to obtain their expertise in these situations.

903.2.11.2   Rubbish and linen chutes.   Linen chutes and rubbish chutes are potential problem areas when it comes to fire safety because of a variety of reasons. They are often used for the transfer of combustible materials, including some levels of hazardous materials. They are also concealed within the building construction, possibly allowing a fire to smolder and grow prior to being detected. Of even more concern, linen and rubbish chutes create vertical openings through a building, allowing for the rapid spread of fire, hot gases, and smoke up through the chute. Therefore, the IBC requires the installation of an automatic sprinkler system at the top of such chutes and in the rooms in which they terminate. Additional sprinklers are required as illustrated in Figure 903-12.

Figure 903-12   Rubbish and linen chute construction and protection.

903.2.11.3   Buildings 55 feet or more in height.   Fire fighting in buildings that are over 55 feet (16,764 mm) in height is difficult, and many jurisdictions do not have the personnel or equipment to rescue occupants and control fires on upper floors. Therefore, this section was developed in recognition of this problem. The provision applies to all buildings other than open parking garages and Group F-2 occupancies.

903.3.1.1   NFPA 13 sprinkler systems.   Where the code requires the installation of an automatic sprinkler system in a building, it typically is referring to a system designed and installed in accordance with the criteria of NFPA 13. This standard is also applicable for those provisions that use a sprinkler system as an alternative to other code requirements. Throughout the code, the use of a sprinkler system “in accordance with Section 903.3.1.1” is referenced. In addition, where an automatic sprinkler system is required by the code with no direct reference to Section 903.3.1.1, the use of an NFPA 13 system is required.

903.3.1.1.1   Exempt locations.   It is the intent of sprinkler protection that sprinklers be installed throughout the structure, including basements, attics, and all other locations specified in the appropriate standard. It is also the intent of the IBC that when an automatic sprinkler system is required throughout, the same meaning is implied. One of the reasons for requiring protection throughout is the possibility of a fire in an unprotected area gaining such a foothold that the automatic sprinkler system would be overpowered. However, over the years, certain areas, locations, or conditions have shown that they require special consideration, and the omission of sprinklers is permitted. In this section, the code itself provides the rationale for the omission of sprinklers.

903.3.1.2   NFPA 13R sprinkler systems.   Although residential sprinkler systems installed in accordance with NFPA 13R may be used to satisfy the requirements of specific institutional and residential occupancies, they are not always recognized as full sprinkler protection for the purposes of exceptions or reductions permitted by other code requirements. However, where specifically mentioned through a reference to this section, such systems may be considered acceptable. Where the code indicates that a benefit can be derived from a sprinkler system installed “in accordance with Section 903.3.1.2,” it intends that an NFPA 13R system can be used for the benefit. An important point is that an NFPA 13R sprinkler system is only permitted in residential-type buildings up to four stories in height.

903.3.1.2.1   Balconies and decks.   Experience has shown that numerous fires in apartment buildings have started from grilling or similar activities on the balconies and patios. Because the NFPA 13R sprinkler standard does not mandate sprinklers in such locations, the code requires such sprinkler protection. The provision is applicable to both dwelling units and sleeping units in buildings of Type VA or VB construction. The automatic sprinkler protection is only required where there is a roof, deck, or balcony directly above a balcony, deck, or patio below. These areas will typically be protected by sidewall-orientation automatic sprinklers. If there is no horizontal element located directly above an exterior balcony, deck, or ground-floor patio, the additional sprinkler protection is not required. See Figure 903-13.

Figure 903-13   Protection of residential deck.

903.3.2   Quick-response and residential sprinklers.   Based on the timely performance of quick-response and residential automatic sprinklers, the code requires that they be installed in those occupancies where response or evacuation may not be immediate because of the condition of the occupants. Therefore, all spaces within a Group I-2 smoke compartment containing care recipient sleeping units and all dwelling units and sleeping units in Group R and I-1 occupancies are to be provided with these types of sprinklers. Similarly, ambulatory care facilities must be provided with quick-response or residential sprinklers in all smoke compartments that contain one or more treatment rooms. Such sprinklers are also required in light-hazard occupancies, where the quantity or combustibility of contents is low. Light-hazard occupancies included places of worship, education facilities, office buildings, museums, and seating areas of restaurants and theaters.

Section 904 Alternative Automatic Fire-Extinguishing Systems

The code permits the use of automatic fire-extinguishing systems other than automatic sprinkler systems for those circumstances approved by the fire code official. However, the use of an alternative system in lieu of a sprinkler system does not gain the benefit of exceptions or reductions in code requirements. Only those buildings or areas protected by automatic sprinkler systems can take advantage of the allowances provided throughout the code.

The installation of automatic fire-extinguishing systems shall be in compliance with this section, which for the most part refers to the appropriate test standard and listing for each of the various types of systems. Those types addressed include wet-chemical, dry-chemical, foam, carbon dioxide, halon, and clean-agent systems.

The inspection and testing of the system is emphasized because of the importance of a fully operating system. Specific items are identified for inspection, including the location, identification, and testing of the audible and visible alarm devices. More specific criteria are also present for the installation and operation of a fire-extinguishing system for a commercial cooking system.

Section 905 Standpipe Systems

A standpipe system is a system of piping, valves, and outlets that is installed exclusively for fire-fighting activities within a building. Standpipes are not considered a viable substitute for an automatic fire-sprinkler system. They are needed in buildings of moderate height and greater, and when used by trained personnel provide an effective means of fighting a fire.

905.3   Required installations.   This section provides the scoping criteria for when a standpipe system must be provided. Figure 905-1 provides the basic requirements for when a standpipe system is required in a building. Building height is the primary consideration for the installation of a standpipe system. The general requirement calls for Class III standpipe systems where the vertical distance between the highest floor level in the building and the lowest level of fire-department vehicle access exceeds 30 feet (9,144 mm). See Figure 905-2. For measurement purposes, it is not necessary to consider any level of fire-department vehicle access that, because of topographic features, makes access to the building from that point impractical or impossible. Several exceptions allow the use of Class I rather than Class III standpipes. Additional standpipe requirements may apply to assembly occupancies, covered and open mall buildings, and stages.

Figure 905-1   Standpipes required.

Figure 905-2   Class III standpipe systems.

905.4   Location of Class I standpipe hose connections.   The code intends that Class I standpipes are for the use of the fire department to fight fires within a building. Thus, the code requires that standpipe outlets be in every required interior exit stairway. The connections are to be located at every intermediate floor level landing of those stairways required by the code. As an alternative, the hose connections are permitted to be located at the floor level landing, but only where specifically allowed by the fire code official. However, the installation of hose connections at intermediate landings is typically preferred in order to avoid congestion at the stairway door. With these locations for standpipe outlets, the fire-department personnel can bring a hose into the stair enclosure and make a hookup to outlets in a relatively protected area. Standpipe connections are not required for exit access stairways permitted to be unenclosed by Section 1019.3, as such stairways provide no protection for fire-department personnel.

Because a horizontal exit provides a barrier having a minimum fire-resistance rating of 2 hours, it is a logical location for Class I standpipe outlets. Such outlets are to be provided on both sides of the horizontal exit wall adjacent to the egress doorways through the horizontal exit wall, regardless of whether or not egress is provided from both directions. An exception permits the omission of the standpipe hose connection at the horizontal exit opening where there is a limited distance between the opening and the stairway hose connection. The elimination of the hose connection is permitted on one side of the horizontal exit, as depicted in Figure 905-3, or on both sides, provided the “100-foot plus 30-foot” distance is not exceeded. The application of the exception is most common where the horizontal exit is provided to allow for the termination of a fire-resistance-rated corridor at an intervening room, or where necessary to address an inadequate number of exits or insufficient egress width. In those cases where the horizontal exit is provided because of a problem with travel distance, the omission of the standpipe connections will seldom be permitted. It should be noted that a standpipe system is not required simply because a horizontal exit occurs within the building. This provision addressing required hose connection locations is only applicable where a horizontal exit is provided in a building described in Section 905.3 as requiring a Class I or Class III standpipe system.

Figure 905-3   Connections at a horizontal exit.

Under unique circumstances, standpipe outlets located in interior exit stairways or at horizontal exit doorways may be a significant distance from some portions of the building. Under these circumstances, additional standpipe outlets must be provided in approved locations when required by the fire code official. Figure 905-4 depicts the required locations of Class I standpipe connections. Standpipe connections required for stages exceeding 1,000 square feet (93 m²) are to be located on each side of the stage, per Figure 905-5.

Figure 905-4   Standpipe connection locations.

Figure 905-5   Class II standpipe locations at stages > 1,000 sq ft.

The enclosure for an interior exit stairway also provides protection for the standpipe and piping system. In those cases where the risers and laterals are not within interior exit stairways, the code requires that they be protected by equivalent fire-resistant construction. The exception to this requirement assumes that the automatic fire-sprinkler system will keep the risers and laterals cool enough so that they will not be damaged by fire.

On those roofs that have a flat enough slope for fire fighters to move about, the code requires at least one roof outlet so that exposure fires can be fought from the roof.

The interconnection of the standpipe risers at the bottom for multiple standpipe systems is intended to increase the reliability.

905.5   Location of Class II standpipe hose connections.   It is the intent of the code to require the location of hose cabinets for Class II standpipes at intervals ensuring that all portions of a building will be within 30 feet (9,144 mm) of a nozzle attached to 100 feet (30,480 mm) of hose. In plan review, this would necessitate allowing for pulling the hose down corridors and through rooms such that several right-angle turns may be necessary before the hose stream can be placed on the fire. Therefore, judgment is necessary in the determination of standpipe locations. One method to account for this type of partitioning in a building where the future location of partitions is unknown is to subtract 30 feet (9,144 mm) from the straight-line distance between the hose cabinet and the remote location and then multiply the remainder by 1.4. If the result is more than 100 feet (30,480 mm), an additional standpipe connection will be required. Figure 905-6 illustrates the location of a Class II standpipe in a building where an office floor has a central corridor with offices on each side. In this particular arrangement, it is obvious from the layout that the one standpipe will suffice.

Figure 905-6   Class II connections.

As there are no scoping provisions in Section 905.3 for a Class II or III standpipe system in a sprinklered Group A occupancy, other than the stage requirements of Section 905.3.4, the provisions of Section 905.5.1 have no application. Therefore, the required locations for Class II standpipe hose connections are limited to those buildings or areas required to have Class III standpipe systems.

Because Class II standpipe systems are charged with water, the code does not require fire-resistive protection. The water within the system is considered adequate to keep the pipe cool enough to prevent damage.

905.6   Location of Class III standpipe hose connections.   Because Class III standpipes are a combination of the benefits of Class I and II systems, containing both 1½-inch (38-mm) outlets for occupant use and 2½-inch (64-mm) outlets for fire department use, it is only logical that they be located so as to serve the building as required for both Class I and II standpipes. Figure 905-7 shows the typical arrangement for a Class III standpipe in a building. Usually, the hose rack for 1½-inch (38-mm) outlets and 2½-inch (64-mm) hose outlets are both located within the stair enclosure. Where the coverage requirements for Class II standpipes are such that interior exit stairway locations will not cover the entire building, laterals are usually run to other locations from hose cabinets in order to provide for the required coverage. In this case, the laterals are not required to be protected, as they are charged with water.

Figure 905-7   Class III standpipe connections.

Class III standpipe systems and their risers and laterals in sprinklered buildings are not required to have fire-resistive protection for the same reason as discussed for Class I standpipes.

Section 907 Fire Alarm and Detection Systems

One of the most effective means of occupant protection in case of a fire incident is the availability of a fire alarm system. An alarm system provides early notification to occupants of the building in the event of a fire, thereby providing a greater opportunity for everyone in the building to evacuate or relocate to a safe area. This section covers all aspects of fire alarm systems and their components.

Unlike most of the provisions of Section 903.2 addressing the required installation of an automatic sprinkler system, those requirements mandating a fire alarm system are typically not applied based on the fire area concept. Manual fire alarm systems are most often required based on the occupant load of the occupancy group under consideration, including any occupants of the same occupancy classification that may be identified in another fire area. Fire areas are not to be used in the application of this section regarding fire alarm systems except where specifically addressed in Sections 907.2.1 (multiple Group A occupancies) and 907.2.2.1 (ambulatory care facilities).

907.2   Where required—new buildings and structures.   Approved fire alarm systems, either manual, automatic, or both manual and automatic, are mandated in those occupancies and areas identified by this section. Where automatic fire detectors are mandated, smoke detectors are to be provided unless normal operations would cause an inaccurate activation of the detector. All automatic fire-detection systems are to be installed in accordance with NFPA 72.

907.2.1   Group A.   Where an assembly occupancy has a sizable occupant load, the safe egress of the occupants becomes an even more important consideration. When the occupant load reaches 300, the code mandates a manual alarm system to provide early notification to the occupants. The IBC also requires portions of a Group E educational occupancy that are occupied for accessory assembly purposes, such as a school lunchroom or library, to have alarms as required for the Group E use, rather than based on the less restrictive requirements mandated for Group A occupancies. In addition, the Group E fire alarm provisions are applicable to those areas within a Group E school building that may be classified as Group A occupancies, such as a gymnasium and/or auditorium. As is the case in many other occupancy classifications, manual alarm boxes are not required in those Group A occupancies where an automatic sprinkler system is installed that will immediately activate the occupant notification appliances (horn/strobes) upon water flow.

Where there are two or more Group A occupancies within the same building, the occupant loads of all such occupancies shall be used in evaluating whether or not a manual fire alarm system is required unless multiple fire areas are created in accordance with Section 707.3.10. Where the fire area concept is used, the alarm requirement is based on the occupant load within each individual fire area. Only those fire areas having a Group A occupant load of 300 or more are required to be provided with a manual fire alarm system.

In assembly occupancies containing much larger occupant loads (1,000 or more people), activation of the required fire alarm system must initiate a prerecorded announcement. The emergency voice/alarm communications system, upon approval of the building official, may also be used for live voice emergency announcements originating from a constantly attended location.

907.2.2   Group B.   Larger business occupancies classified as Group B require the installation of a fire alarm system. Where the total occupant load exceeds 499 persons, or where more than 100 persons occupy Group B spaces above and/or below the lowest level of exit discharge, a manual fire alarm system shall be installed. See Figure 907-1. Similar to exceptions for other occupancies, the manual fire alarm boxes are not required in a sprinklered building where sprinkler water flow activates the notification devices.

Figure 907-1   Required fire alarm system.

Ambulatory care facilities must be provided with a manual fire alarm system as well as an electronically supervised automatic smoke-detection system. The manual fire alarm system must be provided within the fire area in which the ambulatory care facility is located, while the smoke-detection system must serve the care facility as well as the adjoining public areas. In both cases, the presence of an automatic sprinkler system modifies the requirements where occupant notification appliances will activate upon water flow.

907.2.3   Group E.   The IBC follows the philosophy of society in general that our children require special protection when they are not under parental control. Therefore, in addition to the other life-safety requirements for educational occupancies, manual fire alarm systems are required whenever the occupant load of any Group E occupancy is more than 50. In addition, when the building is provided with a smoke-detection or sprinkler system, such systems shall be connected to the building’s fire alarm system. However, the more probable reason for such a low occupant load threshold being established is the exceptional value of such a system in an educational use. Students tend to react quickly and efficiently at the first notification of the alarm system, making safe egress possible. In addition, periodic fire drills reinforce the appropriate egress activity. Where the three conditions are met as listed in Exception 3, manual alarm boxes are not required. Exception 4 also exempts manual fire alarm boxes where, in a sprinklered building, the sprinkler water flow activates the notification appliances and manual activation is possible from a normally occupied location.

The fire alarm system for a Group E occupancy must include an emergency voice/alarm communication system where the occupant load exceeds 100. This type of system will not only provide the necessary notification of occupants under possible fire conditions, but it is also valuable in ensuring the necessary level of life safety inside of the building during a lockdown situation. Because of concerns of school campus safety serving kindergarten through 12th-grade students, it is beneficial to provide an effective means of communication between the established central location and each secured area.

907.2.4   Group F.   In multistory manufacturing occupancies, a fire alarm system is mandated where an aggregate occupant load of 500 or more is housed above and/or below the level of exit discharge. Similar to several other occupancies, the alarm system is necessary where there are very large occupant loads and where those occupants must travel vertically to exit. Application of the provision where occupants are located both above and below the lowest level of exit discharge is similar to that for Group B and M occupancies. In Group F occupancies, a manual fire alarm system is mandated where the aggregate occupant load of those levels, other than the exit discharge level, exceeds 499. Where the building is sprinklered, manual alarm boxes are not required if the water flow of the sprinkler system activates the notification appliances.

907.2.5   Group H.   Only those Group H occupancies associated with semiconductor fabrication or the manufacture of organic coatings need to be provided with a manual alarm system. Areas containing highly toxic gases, organic peroxides, and oxidizers shall be protected by an automatic smoke-detection system.

907.2.6   Group I.   As patients, residents, or inmates of Group I occupancies are asleep during a large portion of the day, Section 907.2.6 provides for early warning of the occupants and staff, thus enhancing life safety. In addition, early response is beneficial because of the lack of mobility of many of the occupants. The general provisions require a manual fire alarm system to be installed in all Group I occupancies, including those classified as Group I-4. However, an automatic smoke-detection system is only required in those occupancies classified as Group I-1, I-2, or I-3. Where a Group I-1, Condition 1 facility is provided with an automatic sprinkler system, only corridors and waiting areas open to such corridors need to be equipped with the smoke-detection system. The corridor smoke-detection system required in Group I-2 facilities may be omitted where the patient sleeping rooms have smoke detectors that provide a visual display on the corridor side of each patient room, as well as a visual and audible alarm at the appropriate nursing station. Another exception exempts the requirement for corridor smoke detection where sleeping-room doors are equipped with automatic door closers having integral smoke detectors on the room side that performs the required alerting functions.

Because of their special nature, in Group I-3 occupancies the provisions for fire alarm systems are greatly expanded. The manual and automatic fire alarm system is to be designed to alert the facility staff. Actuation of an automatic fire-extinguishing system, an automatic sprinkler system, a manual fire alarm box, or a fire detector must initiate an automatic fire alarm signal, which automatically notifies staff. For obvious reasons, manual fire alarm boxes need only be placed at staff-attended locations having direct supervision over the areas where boxes have been omitted. Under certain conditions, the installation of an approved smoke-detection system in resident housing areas is required.

907.2.7   Group M.   The threshold at which a manual fire alarm system is required for a Group M occupancy is the same as that for a Group B occupancy. During that portion of time when the building is occupied, the signal from the fire alarm box or water-flow switch may be designed to only activate a signal at a constantly attended location, rather than provide the customary visual and audible notification. At this location, the use of an emergency voice/alarm communications system can be used to notify the customers of the emergency conditions. This provision is helpful in eliminating those nuisance alarms that may occur because of the presence of fire alarm boxes.

907.2.8   Group R-1.   When asleep, the occupants of residential buildings will usually be unaware of a fire, and it will have an opportunity to spread before being detected. As a result, a majority of fire deaths in residential buildings have occurred because of this delay in detection. It is for this reason that the IBC requires fire alarm systems in addition to smoke detectors in certain residential structures.

In hotels and other buildings designated as Group R-1, the general provisions mandate that both a manual fire alarm system and an automatic fire-detection system be installed. There is an exception that eliminates the requirement for a manual alarm system for such occupancies less than three stories in height where all guestrooms are completely separated by minimum 1-hour fire partitions and each unit has an exit directly to a yard, egress court, or public way. This exception is based on the compartmentation provided by the separations between units and by the relatively rapid means of exiting available to the occupants. Where guestrooms are limited to egress directly to the exterior, early notification, although important, is not critical. A second exception requires the alarm system, but does not mandate the installation of fire alarm boxes throughout buildings that are protected throughout by an approved supervised fire-sprinkler system. There is, however, a need for at least one manual fire alarm box installed in a location approved by the building official. In addition, sprinkler flow must activate the notification appliances. The automatic smoke-detection system required by this section need only be provided within all corridors that serve guestrooms. An exception eliminates the requirement for the automatic fire-detection system in buildings where egress does not occur through interior corridors or other interior spaces.

907.2.9   Group R-2.   Group R-2 buildings such as apartment houses are to be provided with a fire alarm system based on the number of dwelling units and sleeping units, as well as the location of any such units in relationship to the level of exit discharge. Where more than 16 dwelling units or sleeping units are located in a single structure, or where such units are placed at a significant distance vertically from the egress point at ground level, it is beneficial that a detection and notification system be provided. If any one of the three listed conditions exists, the alarm system is required unless exempted or modified by one of the three exceptions. Exceptions similar to those permitted for Group R-1 occupancies apply to Group R-2 buildings as well.

Provisions addressing the installation of an automatic smoke-detection system in Group R-2 college and university buildings are essentially the same as those required for Group R-1 occupancies. The single difference is that the detection system must also be provided in laundry rooms, mechanical equipment rooms, and storage rooms, as well as all common areas located outside of the individual sleeping units or dwelling units. It is intended that these provisions be applicable only to those residential buildings that are operated by a university or college, not privately owned facilities.

907.2.11   Single- and multiple-station smoke alarms.   As indicated in the introduction to the residential fire alarm provisions, residential fire deaths far exceed those of any other building classification. Furthermore, more than one-half of the fire deaths in residential buildings occurred because of a delay in detection that is due to the occupants being asleep at the time of the fire. Thus, the IBC requires smoke alarms in all residential buildings and in certain institutional occupancies. In Group R-1 occupancies, single- or multiple-station smoke alarms are to be installed in all sleeping areas, in any room along the path between the sleeping area and the egress door from the sleeping unit, and on each story within the sleeping unit. In all other residential occupancies, the code requires that smoke detectors be located in the sleeping rooms and on the ceiling or wall of the corridor or area giving access to the sleeping rooms. In addition, at least one smoke alarm shall be installed on each story of a dwelling unit, including basements. Where split levels occur in guestrooms or dwelling units, a smoke alarm need only be installed on the upper level, provided there is no intervening door between the adjacent levels. See Figure 907-2 for illustrations of these provisions.

Figure 907-2   Location of smoke detectors.

In order to notify occupants throughout the dwelling unit or sleeping unit of a potential problem, multiple smoke alarms need to be interconnected. Therefore, when activation of one of the alarm devices takes place, activation of all the alarms must occur. This requirement is also applicable where listed wireless alarms are installed in lieu of physically interconnected smoke alarms. The intent of the code is that the alarms be audible throughout the dwelling, particularly in all sleeping rooms.

907.4.2   Manual fire alarm boxes.   The IBC often requires a manual fire alarm system because of the special occupants or hazards that exist within the building. Manual fire alarm boxes, defined as manually operated devices used to initiate an alarm signal and often referred to as pull stations, are used in many situations as a means for occupants to notify others of a potential fire emergency. This section identifies the proper locations for the installation of these alarm boxes.

In order that manual fire alarm boxes are readily available and accessible to all occupants of the building, they are to be located in close proximity to the point of entry to each exit. This would include placement within 5 feet (1,524 mm) of exterior exit doors, as well as doors entering interior exit stairways and exit passageways, as well as those doors accessing exterior exit stairways and horizontal exits. By placing the boxes adjacent to the exit doors, they will be available to occupants using any of the available exit paths. Additional boxes may be required in extremely large nonsprinklered structures, as the maximum travel distance to the nearest alarm box cannot exceed 200 feet (60,960 mm). A manual fire alarm box, required to be red, must be located in a position so that it can be easily identified and accessed. The maximum height of 48 inches (1,372 mm), measured from the floor to the activating lever or handle, is based on the high-end-reach range limited by the accessibility provisions of ICC A117.1. The minimum height of 42 inches (1,067 mm) keeps the activating mechanism in a position readily viewed and providing ease of manipulation. See Figure 907-3.

Figure 907-3   Manual fire alarm boxes.

Unless the fire alarm system is monitored by a supervising station, a sign must be installed on or adjacent to each manual fire alarm box advising the occupants to notify the fire department. Where a supervised alarm system is in place, notification becomes automatic and the sign is not necessary.

Often it is necessary to develop a means of reducing the accidental or intentional damage or activation of the alarm-initiating device. Therefore, the code gives the fire code official authority to accept protective covers placed over the listed boxes. The alarm box should remain easily identifiable when covered, with adequate instructions for operation.

907.5.2.3   Visible alarms.   Visible alarms are intended to alert hearing-impaired individuals to a fire emergency. Of those locations where audible alarm systems are required, the IBC identifies the specific conditions under which visible alarm-notification appliances are also mandated. In those portions of the building deemed to be public areas or common areas, visual alarms shall be provided in addition to audible alarms. For example, in an office building, the lobby, public corridors, and public restrooms would be considered public areas, whereas the corridors, toilet rooms, break areas, and conference rooms inside an office suite would be considered common use. On the other hand, the individual offices of each employee would be considered private use. Although such offices would not require the installation of visible alarm notification appliances, wiring must be in place for future installation of the alarms as necessary. The potential of additional visible alarm notification appliances is taken into account by requiring at least 20 percent spare capacity for the appliance circuits. Keep in mind that visual alarms are only required in those occupancies where an alarm system is first required by Section 907.2.

Table 907.5.2.3.3 is used to determine the number of sleeping units in Group R-1 or I-1 occupancies that must be provided with visible alarm notification appliances. In both occupancies, the appliances are to be activated by both the in-room smoke alarm and the building’s fire alarm systems. The number of units required to have both visual and audible alarms is based on the total number of units in the building. Not strictly limited to sleeping units, the visible and audible alarm requirements are also applicable where dwelling units are located within a Group R-1 occupancy. In Group R-2 apartment houses and similar occupancies required by the code to have a fire alarm system, provisions must be made for the future installation of visible alarm notification devices as they become necessary.

Section 909 Smoke-Control Systems

The provisions of this section are applicable to the design, construction, testing, and operation of mechanical or passive smoke-control systems only when they are required by other provisions of the IBC. Section 909 specifically exempts smoke- and heat-venting requirements that appear in Section 910 and are discussed in the next section of this handbook. Also, this section states that mechanical smoke-control systems are not required to comply with Chapter 5 of the International Mechanical Code® (IMC®) for exhaust systems unless their normal use would otherwise require compliance.

The provisions of this section establish minimum requirements for the design, installation, and acceptance testing of smoke-control systems, but nothing within the section itself is intended to imply that a smoke-control system is to be installed. Some sections that specifically reference Section 909 are the requirements for atriums (Section 404.5), underground buildings (Section 405.5), and windowless buildings housing Group I-3 occupancies (Section 408.9). Smoke-control systems are intended to provide a protective environment in areas outside that of fire origination to allow for the evacuation or relocation of occupants in a safe manner. The provisions are not designed to protect the contents from damage or assist in fire-fighting activities.

Much of this section is based on the American Society of Heating, Refrigerating, and Air-Conditioning Engineers publication, Design of Smoke Control for Buildings; NFPA publication 92-A, Recommended Practice for Smoke Control Systems Utilizing Barriers and Pressure Differences; and the companion publication 92-B, Technical Guide for Smoke Control Systems in Malls, Atriums, and Large Areas.

Although this section covers both passive and active smoke-control systems, the majority of the material presented addresses the three mechanical methods—pressurization (Section 909.6), airflow (Section 909.7), and exhaust (Section 909.8)—with other sections addressing related subjects such as the design fire; equipment, including fans, ducts, and dampers; power supply; detection and control systems; and the fire fighter’s smoke-control panel.

An important segment of Section 909 addresses acceptance testing of the smoke-control system. Smoke-control system installation requires special inspection testing per Section 909.18.8 to be performed during erection of ductwork and prior to concealment. These inspections are intended for the purpose of testing for leaks, as well as for recording the specific device locations. The latter creates, in effect, as-built drawings for the system. Additional testing and verification prior to occupancy is also mandated. Section 909.18.8.3 requires the work of the special inspector to be documented in a final report. The report shall be reviewed by the responsible registered design professional who is required to certify the work. The final, designer-approved report, together with other information addressed in Section 909.18.9, shall be provided to the fire code official, and a copy shall be maintained on file at the building.

909.20   Smokeproof enclosures.   The provisions of this section identify the methods for complying with Section 1023.11 for the construction of smokeproof enclosures. Smokeproof enclosures are required by Sections 403 and 405 for high-rise buildings and underground buildings, respectively. There are two methods for construction of a ventilated smokeproof enclosure, both of which use an enclosed interior exit stairway or ramp. Either an exterior balcony or a ventilated vestibule can be used as the buffer between the floor of the building and the exit stairs or ramp. In addition, pressurization of the stair or ramp shaft is a permitted alternative.

Unless the pressurization provisions of Section 909.20.5 are used where a smokeproof enclosure is required, the exit path to the stair or ramp shall include a vestibule or an open exterior balcony. The minimum size of the vestibule is illustrated in Figure 909-1. A minimum 2-hour fire-resistance-rated fire barrier separates the smokeproof enclosure from the remainder of the building and also separates the stairway or ramp from the vestibule. The only openings permitted into the enclosure are the required means of egress doors. Construction of an open exterior balcony is based on the required fire-resistance rating for the building’s floor construction, which would typically be 2 hours.

Figure 909-1   Ventilated vestibule.

909.20.3   Natural ventilation alternative.   In this section, the code provides the details of construction where natural ventilation is used to comply with the concept of a smokeproof enclosure. Where an open exterior balcony is provided, fire doors into the stairway or ramp shall comply with Section 716.5. In a vestibule scenario, a similar complying fire door is required between the floor and the vestibule. Between the vestibule and the stairway or ramp, the door assembly need only have a 20-minute fire-protection rating. The necessary vestibule ventilation is to be provided by an opening in the exterior wall at each vestibule. Facing an outer court, yard, or public way at least 20 feet (6,096 mm) in width, the exterior wall opening must provide at least 16 square feet (1.5 m²) of net open area. See Figure 909-2.

Figure 909-2   Natural ventilation.

909.20.4   Mechanical ventilation alternative.   Smokeproof enclosures may also be ventilated by mechanical means. As for naturally ventilated vestibules, a minimum 1½-hour fire door as mandated by Table 716.5 is required between the building and the vestibule, whereas the door between the vestibule and the stairway need only have a 20-minute fire-protection rating. The minimum 1½-hour fire door assembly must also meet the criteria of Section 716.5.3 in order to minimize air leakage between the building and the vestibule.

Individual tightly constructed ducts are used to supply and exhaust air from the vestibule. Air is supplied near the floor level of the vestibule and exhausted near the top. The locations of the supply and exhaust registers are illustrated in Figure 909-3, as is the location for the smoke trap. It is important that doors in the open position do not obstruct the duct openings. The code also allows the use of a performance-based engineered vestibule ventilation system per Section 909.20.4.2.1. In addition to ventilation of the vestibule, air shall be provided and relieved from the stair or ramp shaft as well. By supplying an adequate amount of air while providing a dampered relief opening, a minimum positive pressure of 0.10 inch (29 Pa) of water column shall be maintained in the shaft relative to the vestibule with all doors closed.

Figure 909-3   Vestibule ventilation.

909.20.5   Stair pressurization alternative.   The method addressed in this section applies only to those buildings equipped throughout with an automatic sprinkler system. Through the pressurization of the stair or ramp shaft to a prescribed level, the need for vestibules or open exterior balconies is eliminated. Pressurization levels for the interior exit stairways and ramps shall fall between 0.10 inch (25 Pa) and 0.35 inch (87 Pa) of water column in relationship to the building. With this extent of pressurization, ventilation methods are deemed to be unnecessary.

Section 910 Smoke and Heat Removal

Smoke and hot gases created by a fire rise to the underside of the roof structure above and then build up so as to cause reduced visibility to the point where fire fighting is relatively ineffective. Also, as the hot gases accumulate near the roof structure, the unburned products of combustion become superheated, and if a supply of air is introduced, these hot, unburned products of combustion will ignite violently. Thus, it has been found that it is imperative that industrial and warehouse-type occupancies be provided with smoke and heat vents in the roofs, or as an alternative, a mechanical smoke removal system. Although this section is typically applied to one-story buildings, as well as one-story portions of multistory buildings, smoke and heat removal must also be considered for the top story of multistory structures. In addition, there may be conditions where the space requiring smoke and heat removal is not located at the upper story of the building. In such cases, a mechanical smoke removal system must be provided in lieu of the required smoke and heat vent approach.

910.2   Where required.   The IBC requires smoke and heat venting in specified industrial buildings and warehouses and in any occupancy, as required by the IFC, where high-piled combustible stock or rack storage is provided. The intent is that those occupancies that have a potential to include large areas of combustible materials be provided with the means to rid the building of hot gases and smoke during a fire.

For those buildings containing high-piled combustible storage, the requirements for smoke and heat removal are addressed in the IFC.

It is not uncommon for such large areas to be protected by ESFR sprinklers. Such sprinklers are designed to extinguish a fire, rather than control a fire, through the quick application of large amounts of water. Where ESFR sprinklers are installed, smoke and heat vents are not required.

910.3.2   Smoke and heat vent locations.   As smoke and heat vents are intended to release smoke and hot gases from a fire within the building, the code requires that they be placed a minimum of 20 feet (6,096 mm) from fire walls and from any lot line in order to reduce exposure to adjacent property. Vents shall also be located at least 10 feet (3,048 mm) from fire barriers. Such conditions as roof pitch, curtain location, sprinkler head location, and structural members shall be considered in the location of vents.

Section 911 Fire Command Center

The fire command center is the heart of the fire- and life-safety systems in a complex building. The IBC mandates a fire command center be provided in only very special structures such as high-rise buildings regulated by Section 403. The purpose of the command center is to provide a central location where fire personnel can operate during a fire incident or other emergency. Located as determined by the fire department, the fire command center shall be isolated from the remainder of the building by a minimum 1-hour fire-resistance-rated fire barrier. The code lists those system units, controls, display panels, indicators, devices, furnishings, and plans that are to be contained in the command center.

The provisions of Section 911 are only applicable where some other provision of the code specifically mandates that a fire command center be provided. As an example, Section 909.16 mandates that the fire fighter’s smoke-control panel required for buildings provided with a smoke-control system must be located in a fire command center if the smoke-control system is used to address smoke-protected assembly seating conditions. For other smoke-control applications, a fire command center is not required to be provided.

Section 914 Emergency Responder Safety Features

Section 914 is intended to provide correlation to the current requirements in the IFC for the identification of shaftway hazards and the location of fire protection systems. These requirements are located in Sections 316.2 and 509.1 of the IFC. Section 101.3 of the IBC states that the safety of emergency responders is part of its scope and intent. This new section reinforces the intent by specifying that interior and exterior shaftway hazards be identified as well as the location of fire protection systems, such as fire alarm control units or automatic sprinkler risers.