User note:
About this chapter: Chapter 3 provides the criteria by which buildings and structures are classified into use groups and occupancies. Through the balance of the code, occupancy classification is fundamental in the setting of features of construction; occupant safety requirements, especially building limitations; means of egress; fire protection systems; and interior finishes.
The provisions of this chapter shall control the classification of all buildings and structures as to occupancy and use. Different classifications of occupancy and use represent varying levels of hazard and risk to building occupants and adjacent properties.
Occupancy classification is the formal designation of the primary purpose of the building, structure or portion thereof. Structures shall be classified into one or more of the occupancy groups listed in this section based on the nature of the hazards and risks to building occupants generally associated with the intended purpose of the building or structure. An area, room or space that is intended to be occupied at different times for different purposes shall comply with all applicable requirements associated with such potential multipurpose. Structures containing multiple occupancy groups shall comply with Section 508. Where a structure is proposed for a purpose that is not specifically listed in this section, such structure shall be classified in the occupancy it most nearly resembles based on the fire safety and relative hazard. Occupied roofs shall be classified in the group that the occupancy most nearly resembles, according to the fire safety and relative hazard, and shall comply with Section 503.1.4.
  1. Assembly (see Section 303): Groups A-1, A-2, A-3, A-4 and A-5.
  2. Business (see Section 304): Group B.
  3. Educational (see Section 305): Group E.
  4. Factory and Industrial (see Section 306): Groups F-1 and F-2.
  5. High Hazard (see Section 307): Groups H-1, H-2, H-3, H-4 and H-5.
  6. Institutional (see Section 308): Groups I-1, I-2, I-3 and I-4.
  7. Mercantile (see Section 309): Group M.
  8. Residential (see Section 310): Groups R-1, R-2, R-3 and R-4.
  9. Storage (see Section 311): Groups S-1, S-2 and S-3.
  10. Utility and Miscellaneous (see Section 312): Group U.
Occupancy groups contain subordinate uses having similar hazards and risks to building occupants. Uses include, but are not limited to, those functional designations listed within the occupancy group descriptions in Section 302.1. Certain uses require specific limitations and controls in accordance with the provisions of Chapter 4 and elsewhere in this code.
Assembly Group A occupancy includes, among others, the use of a building or structure, or a portion thereof, for the gathering of persons for purposes such as civic, social or religious functions; recreation, food or drink consumption or awaiting transportation.
A building or tenant space used for assembly purposes with an occupant load of less than 50 persons shall be classified as a Group B occupancy.
The following rooms and spaces shall not be classified as Assembly occupancies:
  1. A room or space used for assembly purposes with an occupant load of less than 50 persons and accessory to another occupancy shall be classified as a Group B occupancy or as part of that occupancy.
  2. A room or space used for assembly purposes that is less than 750 square feet (70 m2) in area and accessory to another occupancy shall be classified as a Group B occupancy or as part of that occupancy.
A room or space used for assembly purposes that is associated with a Group E occupancy is not considered a separate occupancy.
Accessory religious educational rooms and religious auditoriums with occupant loads of less than 100 per room or space are not considered separate occupancies.
Group A-1 occupancy includes assembly uses, usually with fixed seating, intended for the production and viewing of the performing arts or motion pictures including, but not limited to:
  • Motion picture theaters
  • Symphony and concert halls
  • Television and radio studios admitting an audience
  • Theaters
Group A-2 occupancy includes assembly uses intended for food and/or drink consumption including, but not limited to:
  • Banquet halls
  • Casinos (gaming areas)
  • Nightclubs
  • Restaurants, cafeterias and similar dining facilities (including associated commercial kitchens)
  • Taverns and bars
Group A-3 occupancy includes assembly uses intended for worship, recreation or amusement and other assembly uses not classified elsewhere in Group A including, but not limited to:
  • Amusement arcades
  • Art galleries
  • Bowling alleys
  • Community halls
  • Courtrooms
  • Dance halls (not including food or drink consumption)
  • Exhibition halls
  • Funeral parlors
  • Greenhouses for the conservation and exhibition of plants that provide public access.
  • Gymnasiums (without spectator seating)
  • Indoor swimming pools (without spectator seating)
  • Indoor tennis courts (without spectator seating)
  • Lecture halls
  • Libraries
  • Museums
  • Places of religious worship
  • Pool and billiard parlors
  • Waiting areas in transportation terminals
Group A-4 occupancy includes assembly uses intended for viewing of indoor sporting events and activities with spectator seating including, but not limited to:
Group A-5 occupancy includes assembly uses intended for participation in or viewing outdoor activities including, but not limited to:
Business Group B occupancy includes, among others, the use of a building or structure, or a portion thereof, for office, professional or service-type transactions, including storage of records and accounts. Business occupancies shall include, but not be limited to, the following:
  • Airport traffic control towers
  • Ambulatory care facilities
  • Animal hospitals, kennels and pounds
  • Banks
  • Barber and beauty shops
  • Car wash
  • Civic administration
  • Clinic, outpatient
  • Dry cleaning and laundries: pick-up and delivery stations and self-service
  • Educational occupancies for students above the 12th grade
  • Electronic data processing
  • Food processing establishments and commercial kitchens not associated with restaurants, cafeterias and similar dining facilities not more than 2,500 square feet (232 m2) in area.
  • Laboratories: testing and research
  • Motor vehicle showrooms
  • Post offices
  • Print shops
  • Professional services (architects, attorneys, dentists, physicians, engineers, etc.)
  • Radio and television stations
  • Telephone exchanges
  • Training and skill development not in a school or academic program (this shall include, but not be limited to, tutoring centers, martial arts studios, gymnastics and similar uses regardless of the ages served, and where not classified as a Group A occupancy).
Buildings containing lockup facilities, as defined in ORS 169.005(4), shall comply with the following provisions:
  1. Areas containing lockup facilities shall be separated from other rooms, spaces or areas by an approved smoke barrier.
  2. The smoke control zone in which the lockup cells are located shall be provided with an automatic sprinkler system complying with Chapter 9 requirements for Group I-3 occupancies.
  3. The smoke control zone in which the lockup area is located shall be provided with an automatic smoke detection system complying with Chapter 9 requirements for Group I-3 occupancies.
  4. The combined occupant load of the holding cells shall not exceed five.
Educational Group E occupancy includes, among others, the use of a building or structure, or a portion thereof, by six or more persons at any one time for educational purposes through the 12th grade.
Religious educational rooms and religious auditoriums, which are accessory to places of religious worship in accordance with Section 303.1.4 and have occupant loads of less than 100 per room or space, shall be classified as Group A-3 occupancies.
This group includes buildings and structures or portions thereof occupied by more than five children older than 21/2 years of age who receive educational, supervision or personal care services for fewer than 24 hours per day.
Rooms and spaces within places of religious worship providing such day care during religious functions shall be classified as part of the primary occupancy.
A facility having five or fewer children receiving such day care shall be classified as part of the primary occupancy.
A facility such as the above located within a dwelling unit and having five or fewer children receiving such day care shall be classified as a Group R-3 occupancy.

Where located within a detached one- or two-family dwelling or townhouse, the facility shall be permitted to be constructed in accordance with the Residential Code, provided that Section 420.11 is met, and accessibility is provided in accordance with Section 1103.2.12 for newly constructed facilities and Section 3403.4 for existing facilities.
Factory Industrial Group F occupancy includes, among others, the use of a building or structure, or a portion thereof, for assembling, disassembling, fabricating, finishing, manufacturing, packaging, repair or processing operations that are not classified as a Group H hazardous or Group S storage occupancy.
Factory industrial uses that are not classified as Factory Industrial F-2 Low Hazard shall be classified as F-1 Moderate Hazard and shall include, but not be limited to, the following:
  • Aircraft (manufacturing, not to include repair)
  • Appliances
  • Athletic equipment
  • Automobiles and other motor vehicles
  • Bakeries
  • Beverages: over 16-percent alcohol content
  • Bicycles
  • Boats
  • Brooms or brushes
  • Business machines
  • Cameras and photo equipment
  • Canvas or similar fabric
  • Carpets and rugs (includes cleaning)
  • Clothing
  • Construction and agricultural machinery
  • Disinfectants
  • Dry cleaning and dyeing
  • Electric generation plants
  • Electronics
  • Engines (including rebuilding)
  • Food processing establishments and commercial kitchens not associated with restaurants, cafeterias and similar dining facilities more than 2,500 square feet (232 m2) in area.
  • Furniture
  • Hemp products
  • Jute products
  • Laundries
  • Leather products
  • Machinery
  • Metals
  • Millwork (sash and door)
  • Motion pictures and television filming (without spectators)
  • Musical instruments
  • Optical goods
  • Paper mills or products
  • Photographic film
  • Plastic products
  • Printing or publishing
  • Recreational vehicles
  • Refuse incineration
  • Shoes
  • Soaps and detergents
  • Textiles
  • Tobacco
  • Trailers
  • Upholstering
  • Wood; distillation
  • Woodworking (cabinet)
Factory industrial uses that involve the fabrication or manufacturing of noncombustible materials that during finishing, packing or processing do not involve a significant fire hazard shall be classified as F-2 occupancies and shall include, but not be limited to, the following:
  1. Beverages: up to and including 16-percent alcohol content
  2. Brick and masonry
  3. Ceramic products
  4. Foundries
  5. Glass products
  6. Gypsum
  7. Ice
  8. Metal products (fabrication and assembly)
  9. Wood barrel and bottled wine aging facilities in wineries
High-hazard Group H occupancy includes, among others, the use of a building or structure, or a portion thereof, that involves the manufacturing, processing, generation or storage of materials that constitute a physical or health hazard in quantities in excess of those allowed in control areas complying with Section 414, based on the maximum allowable quantity limits for control areas set forth in Tables 307.1(1) and 307.1(2). Hazardous occupancies are classified in Groups H-1, H-2, H-3, H-4 and H-5 and shall be in accordance with this section and the requirements of Section 415. Hazardous materials stored, or used on top of roofs or canopies, shall comply with this code.
TABLE 307.1(1)
MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIALS POSING A PHYSICAL HAZARDa, j, m, n, p
MATERIAL CLASS GROUP WHEN
THE MAXIMUM
ALLOWABLE
QUANTITY IS
EXCEEDED
STORAGEb USE-CLOSED SYSTEMSb USE-OPEN SYSTEMSb
Solid
pounds
(cubic feet)
Liquid
gallons
(pounds)
Gas cubic feet at NTP Solid
pounds
(cubic feet)
Liquid
gallons
(pounds)
Gas cubic feet at NTP Solid
pounds
(cubic feet)
Liquid
gallons
(pounds)
Combustible dust NA H-2 See
Note q
NA NA See
Note q
NA NA See
Note q
NA
Combustible fiberq Loose H-3 (100) NA NA (100) NA NA (20) NA
Baledo (1,000) (1,000) (200)
Combustible liquidc, i II H-2 or H-3 NA 120d, e NA NA 120d NA NA 30d
IIIA H-2 or H-3 330d, e 330d 80d
IIIB NA 13,200e, f 13,200f 3,300f
Cryogenic flammable NA H-2 NA 45d NA NA 45d NA NA 10d
Cryogenic inert NA NA NA NA NL NA NA NL NA NA
Cryogenic oxidizing NA H-3 NA 45d NA NA 45d NA NA 10d
Explosives Division 1.1 H-1 1e, g (1)e, g NA 0.25g (0.25)g NA 0.25g (0.25)g
Division 1.2 H-1 1e, g (1)e, g 0.25g (0.25)g 0.25g (0.25)g
Division 1.3 H-1 or H-2 5e, g (5)e, g 1g (1)g 1g (1)g
Division 1.4 H-3 50e, g (50)e, g 50g (50)g NA NA
Division 1.4G H-3 125e, l NA NA NA NA NA
Division 1.5 H-1 1e, g (1)e, g 0.25g (0.25)g 0.25g (0.25)g
Division 1.6 H-1 1e, g NA NA NA NA NA
Flammable gas Gaseous H-2 NA NA 1,000d, e NA NA 1,000d, e NA NA
Liquefied (150)d, e NA (150)d, e NA
Flammable liquidc IA H-2 or H-3 NA 30d, e NA NA 30d NA NA 10d
IB and IC 120d, e 120d 30d
Flammable liquid, combination (IA, IB, IC) NA H-2 or H-3 NA 120d, e, h NA NA 120d, h NA NA 30d, h
Flammable solid NA H-3 125d, e NA NA 125d NA NA 25d NA
Inert gas Gaseous NA NA NA NL NA NA NL NA NA
Liquefied NA NA NA NL NA NA NL NA NA
Organic peroxide UD H-1 1e, g (1)e, g NA 0.25g (0.25)g NA 0.25g (0.25)g
I H-2 5d, e (5)d, e 1d (1)d 1d (1)d
II H-3 50d, e (50)d, e 50d (50)d 10d (10)d
III H-3 125d, e (125)d, e 125d (125)d 25d (25)d
IV NA NL NL NL NL NL NL
V NA NL NL NL NL NL NL
Oxidizer 4 H-1 1g (1)e, g NA 0.25g (0.25)g NA 0.25g (0.25)g
3k H-2 or H-3 10d, e (10)d, e 2d (2)d 2d (2)d
2 H-3 250d, e (250)d, e 250d (250)d 50d (50)d
1 NA 4,000e, f (4,000)e, f 4,000f (4,000)f 1,000f (1,000)f
Oxidizing gas Gaseous H-3 NA NA 1,500d,e NA NA 1,500d,e NA NA
Liquefied (150)d, e NA (150)d,e NA
Pyrophoric NA H-2 4e, g (4)e, g 50e, g 1g (1)g 10e, g 0 0
Unstable (reactive) 4 H-1 1e, g (1)e, g 10e, g 0.25g (0.25)g 2e, g 0.25g (0.25)g
3 H-1 or H-2 5d, e (5)d, e 50d, e 1d (1)d 10d, e 1d (1)d
2 H-3 50d, e (50)d, e 750d, e 50d (50)d 750d, e 10d (10)d
1 NA NL NL NL NL NL NL NL NL
Water reactive 3 H-2 5d, e (5)d, e NA 5d (5)d NA 1d (1)d
2 H-3 50d, e (50)d, e 50d (50)d 10d (10)d
1 NA NL NL NL NL NL NL
For SI: 1 cubic foot = 0.028 m3, 1 pound = 0.454 kg, 1 gallon = 3.785 L.
NL = Not Limited; NA = Not Applicable; UD = Unclassified Detonable.
  1. For use of control areas, see Section 414.2.
  2. The aggregate quantity in use and storage shall not exceed the quantity listed for storage.
  3. The quantities of alcoholic beverages in retail and wholesale sales occupancies shall not be limited provided the liquids are packaged in individual containers not exceeding 1.3 gallons. In retail and wholesale sales occupancies, the quantities of medicines, foodstuffs or consumer products, and cosmetics containing not more than 50 percent by volume of water-miscible liquids with the remainder of the solutions not being flammable, shall not be limited, provided that such materials are packaged in individual containers not exceeding 1.3 gallons.
  4. Maximum allowable quantities shall be increased 100 percent in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1. Where Note e also applies, the increase for both notes shall be applied accumulatively.
  5. Maximum allowable quantities shall be increased 100 percent when stored in approved storage cabinets, day boxes, gas cabinets, gas rooms or exhausted enclosures or in listed safety cans in accordance with Section 414.18. Where Note d also applies, the increase for both notes shall be applied accumulatively.
  6. Quantities shall not be limited in a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
  7. Allowed only in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
  8. Containing not more than the maximum allowable quantity per control area of Class IA, IB or IC flammable liquids.
  9. The maximum allowable quantity shall not apply to fuel oil storage complying with Section 2802.
  10. Quantities in parentheses indicate quantity units in parentheses at the head of each column.
  11. A maximum quantity of 220 pounds of solid or 22 gallons of liquid Class 3 oxidizers is allowed when such materials are necessary for maintenance purposes, operation or sanitation of equipment when the storage containers and the manner of storage are approved.
  12. Net weight of the pyrotechnic composition of the fireworks. Where the net weight of the pyrotechnic composition of the fireworks is not known, 25 percent of the gross weight of the fireworks, including packaging, shall be used.
  13. For gallons of liquids, divide the amount in pounds by 10 in accordance with Section 414.1.5.1.
  14. For storage and display quantities in Group M and storage quantities in Group S occupancies complying with Section 414.2.5, see Tables 414.2.5(1) and 414.2.5(2).
  15. Densely packed baled cotton that complies with the packing requirements of ISO 8115 shall not be included in this material class.
  16. The following shall not be included in determining the maximum allowable quantities:
    1. Liquid or gaseous fuel in fuel tanks on vehicles.
    2. Liquid or gaseous fuel in fuel tanks on motorized equipment operated in accordance with this code.
    3. Gaseous fuels in piping systems and fixed appliances regulated by the Fuel Gas Code.
    4. Liquid fuels in piping systems and fixed appliances regulated by the Mechanical Code.
  17. Where manufactured, generated or used in such a manner that the concentration and conditions create a fire or explosion hazard based on information prepared in accordance with Section 414.1.3.
TABLE 307.1(2)
MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIALS POSING A HEALTH HAZARDa, c, f, h, i
MATERIAL STORAGEb USE-CLOSED SYSTEMSb USE-OPEN SYSTEMSb
Solid
poundsd, e
Liquid gallons
(pounds)d, e
Gas cubic feet at NTP
(pounds)d
Solid
poundsd
Liquid gallons
(pounds)d
Gas cubic feet at NTP
(pounds)d
Solid
poundsd
Liquid gallons
(pounds)d
Corrosives 5,000 500 Gaseous 810e
Liquefied (150)
5,000 500 Gaseous 810e
Liquefied (150)
1,000 100
Highly Toxic 10 (10) Gaseous 20g
Liquefied (4)g
10 (10) Gaseous 20g
Liquefied (4)g
3 (3)
Toxic 500 (500) Gaseous 810e
Liquefied (150)e
500 (500) Gaseous 810e
Liquefied (150)e
125 (125)
For SI: 1 cubic foot = 0.028 m3, 1 pound = 0.454 kg, 1 gallon = 3.785 L.
  1. For use of control areas, see Section 414.2.
  2. The aggregate quantity in use and storage shall not exceed the quantity listed for storage.
  3. In retail and wholesale sales occupancies, the quantities of medicines, foodstuffs or consumer products, and cosmetics containing not more than 50 percent by volume of water-miscible liquids and with the remainder of the solutions not being flammable, shall not be limited, provided that such materials are packaged in individual containers not exceeding 1.3 gallons.
  4. Maximum allowable quantities shall be increased 100 percent in buildings equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1. Where Note e also applies, the increase for both notes shall be applied accumulatively.
  5. Maximum allowable quantities shall be increased 100 percent where stored in approved storage cabinets, gas cabinets or exhausted enclosures as specified in this code. Where Note d also applies, the increase for both notes shall be applied accumulatively.
  6. For storage and display quantities in Group M and storage quantities in Group S occupancies complying with Section 414.2.5, see Tables 414.2.5(1) and 414.2.5(2).
  7. Allowed only where stored in approved exhausted gas cabinets or exhausted enclosures as specified in this code.
  8. Quantities in parentheses indicate quantity units in parentheses at the head of each column.
  9. For gallons of liquids, divide the amount in pounds by 10 in accordance with Section 414.1.5.1.
An occupancy that stores, uses or handles hazardous materials as described in one or more of the following items shall not be classified as Group H, but shall be classified as the occupancy that it most nearly resembles.
  1. Buildings and structures occupied for the application of flammable finishes, provided that such buildings or areas conform to the requirements of Section 416.
  2. Wholesale and retail sales and storage of flammable and combustible liquids in mercantile occupancies conforming to this code.
  3. Closed piping system containing flammable or combustible liquids or gases utilized for the operation of machinery or equipment.
  4. Cleaning establishments that utilize combustible liquid solvents having a flash point of 140°F (60°C) or higher in closed systems employing equipment listed by an approved testing agency, provided that this occupancy is separated from all other areas of the building by 1-hour fire barriers constructed in accordance with Section 707 or 1-hour horizontal assemblies constructed in accordance with Section 711, or both.
  5. Cleaning establishments that utilize a liquid solvent having a flash point at or above 200°F (93°C).
  6. Liquor stores and distributors without bulk storage.
  7. Refrigeration systems.
  8. The storage or utilization of materials for agricultural purposes on the premises.
  9. Stationary storage battery systems installed in accordance with this code and the Mechanical Code.
  10. Corrosive personal or household products in their original packaging used in retail display.
  11. Commonly used corrosive building materials.
  12. Buildings and structures occupied for aerosol product storage shall be classified as Group S-1, provided that such buildings conform to the requirements of this code.
  13. Display and storage of nonflammable solid and nonflammable or noncombustible liquid hazardous materials in quantities not exceeding the maximum allowable quantity per control area in Group M or S occupancies complying with Section 414.2.5.
  14. The storage of black powder, smokeless propellant and small arms primers in Groups M and R-3 and special industrial explosive devices in Groups B, F, M and S, provided such storage conforms to the quantity limits and requirements prescribed in this code.
  15. Stationary fuel cell power systems installed in accordance with this code and the Mechanical Code.
  16. Capacitor energy storage systems in accordance with this code.
  17. Group B higher education laboratory occupancies complying with Section 428.
Hazardous materials in any quantity shall conform to the requirements of this code, including Section 414.
A permanent building used for the temporary storage of 1.4G (Class C) fireworks, as authorized by a retail sales permit under ORS 480.127, may be classified as either a Group M, Group S-1 or a detached Group U occupancy, provided:
  1. The total amount of 1.4G retail fireworks is less than 5,000 pounds (2268 kg) gross weight; or
  2. Where the building is protected by an approved automatic sprinkler system and the amount of 1.4G retail fireworks is less than 10,000 pounds (4536 kg) gross weight.
Buildings and structures containing materials that pose a detonation hazard shall be classified as Group H-1. Such materials shall include, but not be limited to, the following:
The following occupancies containing explosive materials shall be classified as follows:
  1. Division 1.3 explosive materials that are used and maintained in a form where either confinement or configuration will not elevate the hazard from a mass fire to mass explosion hazard shall be allowed in H-2 occupancies.
  2. Articles, including articles packaged for shipment, that are not regulated as a Division 1.4 explosive under Bureau of Alcohol, Tobacco, Firearms and Explosives regulations, or unpackaged articles used in process operations that do not propagate a detonation or deflagration between articles shall be allowed in H-3 occupancies.
Buildings and structures containing materials that pose a deflagration hazard or a hazard from accelerated burning shall be classified as Group H-2. Such materials shall include, but not be limited to, the following:
  • Class I, II or IIIA flammable or combustible liquids that are used or stored in normally open containers or systems, or in closed containers or systems pressurized at more than 15 pounds per square inch gauge (103.4 kPa).
  • Combustible dusts where manufactured, generated or used in such a manner that the concentration and conditions create a fire or explosion hazard based on information prepared in accordance with Section 414.1.3.
  • Cryogenic fluids, flammable.
  • Flammable gases.
  • Organic peroxides, Class I.
  • Oxidizers, Class 3, that are used or stored in normally open containers or systems, or in closed containers or systems pressurized at more than 15 pounds per square inch gauge (103 kPa).
  • Pyrophoric liquids, solids and gases, nondetonable.
  • Unstable (reactive) materials, Class 3, nondetonable.
  • Water-reactive materials, Class 3.
Buildings and structures containing materials that readily support combustion or that pose a physical hazard shall be classified as Group H-3. Such materials shall include, but not be limited to, the following:
Buildings and structures containing materials that are health hazards shall be classified as Group H-4. Such materials shall include, but not be limited to, the following:
Semiconductor fabrication facilities and comparable research and development areas in which hazardous production materials (HPM) are used and the aggregate quantity of materials is in excess of those listed in Tables 307.1(1) and 307.1(2) shall be classified as Group H-5. Such facilities and areas shall be designed and constructed in accordance with Section 415.11.
Buildings and structures containing a material or materials representing hazards that are classified in one or more of Groups H-1, H-2, H-3 and H-4 shall conform to the code requirements for each of the occupancies so classified.
Institutional Group I occupancy includes, among others, the use of a building or structure, or a portion thereof, in which care or supervision is provided to persons who are or are not capable of self-preservation without physical assistance or in which persons are detained for penal or correctional purposes or in which the liberty of the occupants is restricted. Institutional occupancies shall be classified as Group I-1, I-2, I-3 or I-4.
Institutional Group I-1 occupancy shall include buildings, structures or portions thereof for more than 16 persons, excluding staff, who reside on a 24-hour basis in a supervised environment and receive custodial care. Buildings of Group I-1 shall be classified as one of the occupancy conditions specified in Section 308.2.1 or 308.2.2.
This occupancy condition shall include buildings in which all persons receiving custodial care who, without any assistance, are capable of responding to an emergency situation to complete building evacuation.

This group shall include, but not be limited to, the following:

Congregate living facilities

Halfway houses

Social rehabilitation facilities
This occupancy condition shall include buildings subject to licensure by the Oregon Department of Human Services in which there are any persons receiving custodial care who require limited verbal or physical assistance while responding to an emergency situation to complete building evacuation. This group shall include, but not be limited to, the following:

Alcohol and drug centers

Assisted living facilities with or without a Memory

Care Endorsement


Residential care facilities with or without a Memory

Care Endorsement


Residential treatment facilities

Group homes and facilities
A facility housing not fewer than six and not more than 16 persons receiving custodial care shall be classified as Group R-4.
A facility with five or fewer persons receiving custodial care shall be classified as Group R-3 or shall comply with the Residential Code provided an automatic sprinkler system is installed in accordance with Section 903.3.1.3.
Institutional Group I-2 occupancy shall include buildings and structures used for medical care on a 24-hour basis for more than five persons who are incapable of self-preservation. This group shall include, but not be limited to, the following:
Buildings of Group I-2 shall be classified as one of the occupancy conditions specified in Section 308.3.1.1 or 308.3.1.2.
This occupancy condition shall include facilities that provide nursing and medical care but do not provide emergency care, surgery, obstetrics or in-patient stabilization units for psychiatric or detoxification, including but not limited to nursing homes and foster care facilities.
This occupancy condition shall include facilities that provide nursing and medical care and could provide emergency care, surgery, obstetrics or in-patient stabilization units for psychiatric or detoxification, including but not limited to hospitals.
A facility with five or fewer persons receiving medical care shall be classified as Group R-3 or shall comply with the Residential Code provided an automatic sprinkler system is installed in accordance with Section 903.3.1.3.
Institutional Group I-3 occupancy shall include buildings and structures that are inhabited by more than five persons who are under restraint or security. A Group I-3 facility is occupied by persons who are generally incapable of self-preservation due to security measures not under the occupants' control. This group shall include, but not be limited to, the following:
  • Correctional centers
  • Detention centers
  • Jails
  • Prerelease centers
  • Prisons
  • Reformatories
Buildings of Group I-3 shall be classified as one of the occupancy conditions specified in Sections 308.4.1 through 308.4.5 (see Section 408.1).
This occupancy condition shall include buildings in which free movement is allowed from sleeping areas, and other spaces where access or occupancy is permitted, to the exterior via means of egress without restraint. A Condition 1 facility is permitted to be constructed as Group R.
This occupancy condition shall include buildings 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.
This occupancy condition shall include buildings in which free movement is allowed within individual smoke compartments, such as within a residential unit comprised of individual sleeping units and group activity spaces, where egress is impeded by remote-controlled release of means of egress from such a smoke compartment to another smoke compartment.
This occupancy condition shall include buildings in which free movement is restricted from an occupied space. Remote-controlled release is provided to permit movement from sleeping units, activity spaces and other occupied areas within the smoke compartment to other smoke compartments.
This occupancy condition shall include buildings in which free movement is restricted from an occupied space. Staff-controlled manual release is provided to permit movement from sleeping units, activity spaces and other occupied areas within the smoke compartment to other smoke compartments.
Institutional Group I-4 occupancy shall include buildings and structures occupied by more than five persons of any age who receive custodial care for fewer than 24 hours per day by persons other than parents or guardians, relatives by blood, marriage or adoption, and in a place other than the home of the person cared for. This group shall include, but not be limited to, the following:
  • Adult day care
  • Child day care
A child day care facility that provides care for more than five but not more than 100 children 21/2 years or less of age, where the rooms in which the children are cared for are located on a level of exit discharge serving such rooms and each of these child care rooms has an exit door directly to the exterior, shall be classified as Group E.
Rooms and spaces within places of religious worship providing such care during religious functions shall be classified as part of the primary occupancy.
A facility having five or fewer persons receiving custodial care shall be classified as part of the primary occupancy.
A facility such as the above within a dwelling unit and having five or fewer persons receiving custodial care shall be classified as a Group R-3 occupancy or shall comply with the Residential Code.
A registered or certified family child care facility, as defined in ORS 329A, located within a dwelling shall be classified as a Group R-3 occupancy. Where located within a detached one- or two-family dwelling or townhouse, the facility shall be permitted to be constructed in accordance with the Residential Code, provided that Section 420.11 is met, and accessibility is provided in accordance with Section 1103.2.12 for newly constructed facilities and Section 3403.4 for existing facilities.
Mercantile Group M occupancy includes, among others, the use of a building or structure or a portion thereof for the display and sale of merchandise, and involves stocks of goods, wares or merchandise incidental to such purposes and accessible to the public. Mercantile occupancies shall include, but not be limited to, the following:
  • Department stores
  • Drug stores
  • Markets
  • Greenhouses for display and sale of plants that provide public access.
  • Motor fuel-dispensing facilities
  • Retail or wholesale stores
  • Sales rooms
The aggregate quantity of nonflammable solid and nonflammable or noncombustible liquid hazardous materials stored or displayed in a single control area of a Group M occupancy shall not exceed the quantities in Table 414.2.5(1).
Residential Group R includes, among others, the use of a building or structure, or a portion thereof, for sleeping purposes when not classified as an Institutional Group I or when not regulated by the Residential Code.
Residential Group R-1 occupancies containing sleeping units where the occupants are primarily transient in nature, including:
Residential Group R-2 occupancies containing sleeping units or more than two dwelling units where the occupants are primarily permanent in nature, including:
     Group R-2 occupancies providing 21 or more housing units for low-income elderly, which are financed in whole or in part by federal or state funds, shall contain a multiservice room adequate in size to seat all the tenants (ORS 455.425). The multiservice room shall include adjacent toilet facilities for both sexes; a service area with a kitchen sink, countertop, and upper and lower cabinets; and a storage room sized to store tables, chairs or benches, and janitorial supplies and tools. The multiservice room and accessory rooms shall be accessible in accordance with Chapter 11.
Residential Group R-3 occupancies where the occupants are primarily permanent in nature and not classified as Group R-1, R-2, R-4 or I, including:
A care facility located within a detached one- or two-family dwelling or townhouse and having five or fewer persons receiving care shall be permitted to be constructed in accordance with the Residential Code, provided that Section 420.11 is met, and accessibility is provided in accordance with Section 1103.2.12 for newly constructed facilities and Section 3403.4 for existing facilities.
A registered or certified family child care facility, as defined in ORS 329A, located within a dwelling shall be classified as a Group R-3 occupancy. Where located within a one- or two-family dwelling or townhouse the care facility shall be permitted to be constructed in accordance with the Residential Code, provided that Section 420.11 is met, and accessibility is provided in accordance with Section 1103.2.12 for newly constructed facilities and Section 3403.4 for existing facilities.
Owner-occupied lodging houses with five or fewer guest rooms and 10 or fewer total occupants shall be permitted to be constructed in accordance with the Residential Code.
Residential Group R-4 occupancy shall include buildings, structures or portions thereof for more than five but not more than 16 persons, excluding staff, who reside on a 24-hour basis in a supervised residential environment and receive custodial care. Buildings of Group R-4 shall be classified as one of the occupancy conditions specified in Section 310.5.1 or 310.5.2.
     Group R-4 occupancies shall meet the requirements for construction as defined for Group R-3, except as otherwise provided for in this code.
This occupancy condition shall include buildings in which all persons receiving custodial care, without any assistance, are capable of responding to an emergency situation to complete building evacuation. This group shall include, but not be limited to, the following:

Congregate living facilities

Halfway houses

Social rehabilitation facilities
This occupancy condition shall include buildings subject to licensure by the Oregon Department of Human Services in which there are any persons receiving custodial care who require limited verbal or physical assistance while responding to an emergency situation to complete building evacuation. This group shall include, but not be limited to, the following:

Alcohol and drug centers

Assisted living facilities with or without a Memory

Care Endorsement


Residential care facilities with or without a Memory

Care Endorsement


Residential treatment facilities

Group homes and facilities
Storage Group S occupancy includes, among others, the use of a building or structure, or a portion thereof, for storage that is not classified as a hazardous occupancy.
A room or space used for storage purposes that is accessory to another occupancy may be classified as part of that occupancy.
Storage Group S-1 occupancies are buildings occupied for storage uses that are not classified as Group S-2, including, but not limited to, storage of the following:
  • Aerosol products, Levels 2 and 3
  • Aircraft hangar (storage and repair)
  • Bags: cloth, burlap and paper
  • Bamboos and rattan
  • Baskets
  • Belting: canvas and leather
  • Books and paper in rolls or packs
  • Boots and shoes
  • Buttons, including cloth covered, pearl or bone
  • Cardboard and cardboard boxes
  • Clothing, woolen wearing apparel
  • Cordage
  • Dry boat storage (indoor)
  • Furniture
  • Furs
  • Glues, mucilage, pastes and size
  • Grains
  • Horns and combs, other than celluloid
  • Leather
  • Linoleum
  • Lumber
  • Motor vehicle repair garages complying with the maximum allowable quantities of hazardous materials listed in Table 307.1(1) (see Section 406.8)
  • Photo engravings
  • Resilient flooring
  • Self-service storage facility (mini-storage)
  • Silks
  • Soaps
  • Sugar
  • Tires, bulk storage of
  • Tobacco, cigars, cigarettes and snuff
  • Upholstery and mattresses
  • Wax candles
Storage Group S-2 occupancies include, among others, buildings used for the storage of noncombustible materials such as products on wood pallets or in paper cartons with or without single thickness divisions; or in paper wrappings. Such products are permitted to have a negligible amount of plastic trim, such as knobs, handles or film wrapping. Group S-2 storage uses shall include, but not be limited to, storage of the following:
  • Asbestos
  • Beverages up to and including 16-percent alcohol in wood barrels, metal, glass or ceramic containers
  • Cement in bags
  • Chalk and crayons
  • Dairy products in nonwaxed coated paper containers
  • Dry cell batteries
  • Electrical coils
  • Electrical motors
  • Empty cans
  • Food products
  • Foods in noncombustible containers
  • Fresh fruits and vegetables in nonplastic trays or containers
  • Frozen foods
  • Glass
  • Glass bottles, empty or filled with noncombustible liquids
  • Gypsum board
  • Inert pigments
  • Ivory
  • Meats
  • Metal cabinets
  • Metal desks with plastic tops and trim
  • Metal parts
  • Metals
  • Mirrors
  • Oil-filled and other types of distribution transformers
  • Parking garages, open or enclosed
  • Porcelain and pottery
  • Stoves
  • Talc and soapstones
  • Washers and dryers
Storage Group S-3 occupancies include, among others, mausoleums and columbariums. Except where specific provisions are made in Section 456, other requirements of this code shall apply.
Buildings and structures of an accessory character and miscellaneous structures not classified in any specific occupancy shall be constructed, equipped and maintained to conform to the requirements of this code commensurate with the fire and life hazard incidental to their occupancy. Group U shall include, but not be limited to, the following:
  • Agricultural buildings
  • Aircraft hangars, accessory to a one- or two-family residence (see Section 412.4)
  • Barns
  • Carports
  • Communication equipment structures with a gross floor area of less than 1,500 square feet (139 m2)
  • Fences more than 6 feet (1829 mm) in height
  • Grain silos, accessory to a residential occupancy
  • Livestock shelters
  • Private garages
  • Retaining walls
  • Sheds
  • Stables
  • Tanks
  • Towers
Greenhouses not classified as another occupancy shall be classified as Group U.