User note:
About this appendix: Appendix A classifies buildings, structures and portions thereof by their primary use in order to facilitate design and construction in accordance with other provisions of this code. When determining the design performance level, the building or structure needs to be assigned to a performance group. This appendix provides guidance as to the use group or occupancy classification of the building to determine the performance group when applying Table 303.1.
To identify the primary uses of buildings, structures and portions of buildings and structures; to identify risk factors associated with these uses; and to facilitate design and construction in accordance with other provisions of this code. These preliminary assumptions must be documented and verified as valid in any particular case.
In determining the primary use and occupancy classification of a building, structure or portion of a building or structure, the following shall be considered.
The principal purpose or function of the building or structure.
The hazard-related risk(s) to the users.
- In determining the principal purpose or function of the building or structure, the use and occupancy classifications found in the International Building Code shall be used.
- In determining the hazard-related risk(s) to users of buildings and structures, the following shall be considered:
- 2.1. The nature of the hazard, whether it is likely to originate internal or external to the structure, and how it may impact the occupants, the structure and the contents.
- 2.2. The number of persons normally occupying, visiting, employed in or otherwise using the building, structure or portion of the building or structure.
- 2.3. The length of time the building is normally occupied by people.
- 2.4. Whether people normally sleep in the building.
- 2.5. Whether the building occupants and other users are expected to be familiar with the building layout and means of egress.
- 2.6. Whether a significant percentage of the building occupants are, or are expected to be, members of vulnerable population groups such as infants, young children, elderly persons, persons with physical disabilities, persons with mental disabilities or persons with other conditions or impairments that could affect their ability to make decisions, egress without the physical assistance of others or tolerate adverse conditions.
- 2.7. Whether a significant percentage of building occupants and other users have familiar or dependent relationships.
Buildings shall be classified in accordance with the International Building Code and as modified by applying the risk considerations in Section A102.1.2.
A building, structure or portion of a building or structure in which persons gather for purposes such as civic, social or religious functions, recreation, food and drink consumption, or awaiting transportation. Unless otherwise modified under a specific sub-use classification, occupants, visitors and employees shall be assumed to be awake, alert, predominantly able to exit without the assistance of others, and unfamiliar with the building or structure. Vulnerable populations of many types may be expected to be present; however, the buildings are normally occupied for only short periods of time. It shall be assumed that:
- Risks of injury and health assumed by occupants and visitors during their use of the building or structure are predominantly involuntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in an assembly building, structure or portion thereof are high.
Assembly uses, usually with fixed seating, intended for the production and viewing of the performing arts or motion pictures.
Assembly uses intended for food and drink consumption. It may be assumed that some portion of the population within this use group will be consuming alcohol, that loud and distracting sounds will be present, and that flashing lights may be present under normal conditions.
Assembly uses intended for worship, recreation or amusement, and other assembly uses not classified elsewhere in Use Group A.
Assembly uses intended for viewing of indoor sporting events and activities with spectator seating. It may be assumed that some portion of the population within this use group will be consuming alcohol, that loud and distracting sounds will be present and that flashing lights may be present under normal conditions.
Assembly uses intended for participation in or viewing of outdoor activities. It may be assumed that some portion of the population within this use group will be consuming alcohol, that loud and distracting sounds will be present and that flashing lights may be present under normal conditions.
A building, structure or portion of a building or structure for office, professional or service-type transactions, including storage of records and accounts. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risks of injury and health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in a business building, structure or portion thereof are neither unusually high nor unusually low.
A building, structure or portion of a building or structure in which six or more persons, generally under the age of 18, gather for formal educational purposes. It shall be assumed that:
- Occupants, visitors and employees are awake, alert and familiar with the building or structure.
- Persons under the age of 10 will require assistance in exiting, and that persons 10 years of age and older will predominantly be able to exit without assistance.
- Risks of injury and health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in an educational building, structure or portion thereof are high.
A building, structure or portion of a building or structure that involves assembling, disassembling, fabricating, finishing, manufacturing, packaging, repair or processing operations that are not classified as hazardous. Unless otherwise modified under a specific sub-use classification, occupants, visitors and employees shall be assumed to be awake, alert, predominantly able to exit without the assistance of others, and familiar with the building or structure. It shall be assumed that:
- Risks of injury and health assumed by occupants, visitors and employees during their use of the building or structure are predominantly voluntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in a factory-industrial building, structure or portion thereof are neither unusually high nor unusually low.
Factory-industrial uses that are not classified as F-2, low hazard.
Factory-industrial uses that involve the fabrication or manufacturing of noncombustible materials, which during finishing, packing or processing, do not involve a significant fire hazard.
A building, structure or portion of a building or structure that involves the manufacturing, processing, generation or storage of corrosive, highly toxic, highly combustible, flammable or explosive materials that constitute a high fire or explosion hazard, including loose combustible fibers, dust and unstable materials. Unless otherwise modified under a specific subuse classification, occupants, visitors and employees shall be assumed to be awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure. It shall be assumed that:
- Risks of injury and health assumed by occupants, visitors and employees during their use of the building or structure are predominantly voluntary.
- The occupants, visitors and employees have little control over hazards imposed on them during their use of the building or structure.
- Public expectations regarding the protection afforded those occupying, visiting or working in a hazardous building, structure or portion thereof are high.
A building or structure that contains materials that present a detonation hazard.
A building or structure that contains materials that present a deflagration hazard or a hazard of accelerated burning.
A building or structure that contains significant quantities of materials that readily support combustion or that present a significant physical hazard.
A building or structure that contains significant quantities of materials that are health hazards.
A semiconductor fabrication facility or comparable research and development area in which hazardous production materials (HPM) are used and the aggregate quantity poses a significant hazard.
A building, structure or portion of a building or structure in which persons having physical or mental limitations because of health or age are harbored for medical treatment or other care or treatment, or in which people are detained for penal or correctional purposes, or in which the liberty of the occupants is restricted. Unless otherwise modified under a specific subuse classification, occupants and visitors shall not be assumed to be awake, alert, able to exit without the assistance of others, or be familiar with the building or structure. Employees shall be assumed to be awake, alert, predominantly able to exit without the assistance of others, and familiar with the building or structure. It shall be assumed that:
- Risks of injury and health assumed by occupants and visitors during their use of the building or structure are predominantly involuntary.
- Risks of injury and health assumed by employees during their use of the building or structure are predominantly voluntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in an institutional building, structure or portion thereof are moderate to high.
A building, structure or portion of a building or structure housing more than 16 persons on a 24-hour basis who, because of age, mental disability or other reasons, live in a supervised residential environment where personal care services are provided. It shall be assumed that:
- The occupants are mostly capable of responding to an emergency situation without physical assistance from staff.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally moderate.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-1 institutional building, structure or portion thereof are high.
A building, structure or portion of a building or structure used for medical, surgical, psychiatric, nursing or custodial care on a 24-hour basis for more than five persons who are not capable of self-preservation. It shall be assumed that:
- The occupants are incapable of responding to an emergency situation without physical assistance from staff.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally high.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-2 institutional building, structure or portion thereof are very high.
A building or structure that is inhabited by more than five persons who are under some restraint security.
A building in that free movement is allowed from sleeping areas and other areas where access or occupancy is permitted to the exterior via a means of egress without restraint. It shall be assumed that:
- The occupants are mostly incapable of responding to an emergency situation without physical assistance from staff.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally low.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-3.1 institutional building, structure or portion thereof are neither unusually high nor unusually low.
A building in which free movement is allowed from sleeping areas and any other occupied smoke compartment to one or more other smoke compartments. Egress to the exterior is impeded by locked exits. It shall be assumed that:
- The occupants are incapable of responding to an emergency situation without physical assistance from staff (for example, door release).
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally moderate.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-3.2 institutional building, structure or portion thereof are neither unusually high nor unusually low.
A building in which free movement is allowed within individual smoke compartments, and where egress is impeded by remote-controlled release of means of egress from one smoke compartment to another smoke compartment. It shall be assumed that:
- The occupants are incapable of responding to an emergency situation without physical assistance from staff (for example, door release).
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally moderate.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-3.3 institutional building, structure or portion thereof are neither unusually high nor unusually low.
A building in which free movement is restricted from an occupied space. Remote-controlled release is provided to permit movement from sleeping rooms, activity spaces and other occupied areas within the smoke compartment to other smoke compartments. It shall be assumed that:
- The occupants are incapable of responding to an emergency situation without physical assistance from staff (for example, door release).
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally high.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-3.4 institutional building, structure or portion thereof are neither unusually high nor unusually low.
Buildings in which free movement is restricted from an occupied space. Staff-controlled release is provided to permit movement from sleeping rooms, activity spaces and other occupied areas within the smoke compartment to other smoke compartments. It shall be assumed that:
- The occupants are incapable of responding to an emergency situation without physical assistance from staff (for example, door release).
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally high.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-3.5 institutional building, structure or portion thereof are neither unusually high nor unusually low.
A building or structure occupied by persons of any age who receive custodial care for less than 24 hours by individuals other than parents or guardians, relatives by blood, marriage or adoption, and in a place other than the home of the person receiving care.
A facility that provides accommodation for more than five unrelated adults and provides supervision and personal care services. It shall be assumed that:
- The occupants are mostly capable of responding to an emergency situation without physical assistance from staff.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally moderate.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-4.1 institutional building, structure or portion thereof are high.
A facility that provides accommodation for more than five children, 21/2 years of age or less. It shall be assumed that:
- The occupants are incapable of responding to an emergency situation without physical assistance from staff.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are nominally high.
- Public expectations regarding the protection afforded those occupying, visiting or working in an I-4.2 institutional building, structure or portion thereof are very high.
A building, structure or portion of a building or structure for the display and sale of merchandise that involves stocks of goods, wares or merchandise incidental to such purposes and available to the public. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in a mercantile building, structure or portion thereof are neither unusually high nor unusually low.
A building, structure or portion of a building or structure for sleeping accommodations where not classified as institutional.
A residential occupancy where occupants are primarily transient in nature (staying less than 30 days).
It shall be assumed that:
- Occupants and visitors are not awake, alert, able to exit without the assistance of others or familiar with the building or structure.
- Employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risks of injury and health assumed by occupants and visitors during their use of the building or structure are predominantly involuntary.
- Risk of injury and risk to health assumed by employees during their use of the building or structure are predominantly voluntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in the R-1.1 residential building, structure or portion thereof are high.
It shall be assumed that:
- Occupants and visitors are not awake, alert, able to exit without the assistance of others or familiar with the building or structure.
- Employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are predominantly involuntary.
- Risk of injury and risk to health assumed by employees during their use of the building or structure are predominantly voluntary and moderate.
- Public expectations regarding the protection afforded those occupying, visiting or working in the R-1.2 residential building, structure or portion thereof are moderate.
A residential occupancy where the occupants are primarily permanent in nature and that contains more than two dwelling units. It shall be assumed that:
- Occupants and visitors are not awake, alert or able to exit without the assistance of others.
- Occupants and visitors are familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are predominantly voluntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in the R-2 residential building, structure or portion thereof are neither unusually high nor unusually low.
A residential occupancy where the occupants are primarily permanent in nature, not classified as R-1 or R-2, and that does not contain more than two dwelling units. It shall be assumed that:
- Occupants and visitors are not awake, alert or able to exit without the assistance of others.
- Occupants and visitors are familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are predominantly voluntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in the R-3 residential building, structure or portion thereof are neither unusually high nor unusually low.
A residential occupancy that includes buildings arranged for occupancy as residential care/assisted living facilities including not more than 16 occupants excluding staff. It shall be assumed that:
- Occupants and visitors are not awake, alert, able to exit without the assistance of others or familiar with the building or structure.
- Employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants and visitors during their use of the building or structure are predominantly involuntary.
- Risk of injury and risk to health assumed by employees during their use of the building or structure are predominantly voluntary and moderate.
- Public expectations regarding the protection afforded those occupying, visiting or working in the R-4 residential building, structure or portion thereof are high.
A building or structure that may not be fully described or considered under the other use group classifications or for which unique or special consideration shall be given.
A building or structure not exceeding three floor levels in height, enclosing a number of occupancies and tenancies use groups, wherein two or more tenants have a main entrance into one or more roofed or covered common pedestrian areas shared by the tenants. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A building or structure having occupied floors located more than 75 feet (22 860 mm) above the lowest level of fire department vehicle access that contain any use group classification or combination of use group classifications. The assumed risk levels, hazard levels and occupant characteristics shall be appropriate to the uses present within the building, and the structural, fire protection and means-of-egress features shall be designed to accommodate the highest risk level present in the building. It shall be assumed that public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are high.
An opening through two or more floor levels of a building defined by other use groups, other than for enclosed stairways, elevators, hoistways, escalators, plumbing, electrical, air-conditioning or other equipment, that is closed at the top and not defined as a mall. Risk and hazard levels shall correspond to the use group of the building within which the atrium is located.
Building spaces having a floor level used for human occupancy more than 30 feet (9140 meters) or more than one story below the level of exit discharge. Risk and hazard levels shall correspond to the use group of the building.
A structure that is used exclusively for the parking or storage of private motor vehicles, where for natural ventilation purposes, the exterior of the structure has uniformly distributed openings of not less than 20 percent of the total perimeter wall area of each tier on two or more sides; that employs parking machines, lifts, elevators or other mechanical devices for vehicles moving from and to street level; and in which public occupancy is prohibited above street level. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and unfamiliar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A structure that is used exclusively for the parking or storage of private motor vehicles, where for natural ventilation purposes, the exterior of the structure has uniformly distributed openings of not less than 20 percent of the total perimeter wall area of each tier on two or more sides; that employs a series of interconnecting ramps between tiers permitting the movement of vehicles under their own power from and to street level. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and unfamiliar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A structure used exclusively for the parking or storage of private motor vehicles that does not meet the requirements of SP-5 or SP-6. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and unfamiliar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A facility containing storage tanks, pumps and attendant facilities for the purpose of fueling gasoline- and diesel-powered motor vehicles; and a building, structure or portion of a building or structure that is used for changing tires, oil, filters or other minor repair of motor vehicles, and for motor vehicle safety and emissions inspections. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A building, structure or portion of a building or structure that is used for painting, body and fender work, engine overhauling or other major repair of motor vehicles. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A room in which ribbon-type cellulose, acetate or other safety film is utilized in conjunction with electric arc, xenon or other light-source projection equipment that, when operated, may result in the production of hazardous gases, dust or radiation. It shall be assumed that:
- Visitors and employees are awake, alert and predominantly able to exit without the assistance of others.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
Spaces within buildings and structures, often raised above floor level, used for entertainment, presentations and similar purposes. It shall be assumed that:
- Users are awake, alert and predominantly able to exit without the assistance of others.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A temporary, permanent or mobile building or structure that is occupied for amusement, entertainment or educational purposes and that contains a device or system that conveys passengers or provides a walkway along, around or over a course, in any direction, so arranged that means of egress are not readily apparent because of visual or audible distractions, or are intentionally confounded, or are not readily available because of the nature of the attraction or the mode of conveyance through the building or structure. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and unfamiliar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and high.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are high.
A building, structure or portion of a building or structure used for air traffic control, aircraft storage and maintenance, or helicopter landing and fueling. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly involuntary and low.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A building, structure or portion of a building or structure for storage that is not classified as hazardous. Unless otherwise modified under a specific sub-use classification, occupants, visitors and employees shall be assumed to be awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure. It shall be assumed that:
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly voluntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.
A building or structure occupied for storage uses, which may contain materials that present moderate fire, explosion, corrosive, toxic or health hazards.
A building or structure occupied for storage uses that does not contain materials that present significant fire, explosion, corrosive, toxic or health hazards.
A building, structure or portion of a building or structure that is accessory to one- and two-family residential buildings, is used to house livestock and livestock feed or is not covered by other provisions of this section. It shall be assumed that:
- Occupants, visitors and employees are awake, alert, predominantly able to exit without the assistance of others and familiar with the building or structure.
- Risk of injury and risk to health assumed by occupants, visitors and employees during their use of the building or structure are predominantly voluntary.
- Public expectations regarding the protection afforded those occupying, visiting or working in such a building, structure or portion thereof are neither unusually high nor unusually low.