780 CMR 3.00 USE AND OCCUPANCY CLASSIFICATION

780 CMR 3.00USE AND OCCUPANCY CLASSIFICATION780 CMR 301.0 GENERAL301.1 Scope. The provisions of 780 CMR 3.00shall control the classification of all buildings andstructures as to use and occupancy.301.1.1 The ICC International Fire Code (IFC),the ICC International Mechanical Code (IMC)and the Specific Specialized Code - The Board ofFire Prevention Regulations (527 CMR).780 CMR contains design and constructionrequirements for all USE Group buildings andtheir building permittable systems and alsoreferences additional applicable design andconstruction requirements of the IFC and the IMCfor the various USE Groups and industrialprocesses within such USE Groups, including HUSES. It is the intention in referencing the IFCand the IMC that only the IFC and IMCrequirements narrow to Building Code matters;i.e., USE Group classification, general buildinglimitations of height and area, fireresistantmaterials and construction, interior finishes,required fire protection systems (otherwise notspecifically regulated by 527 CMR), means ofegress, interior environment, energy conservation,exterior wall coverings, roof and roof coverings,structural loads, structural tests and inspections,foundations and retaining walls, constructionmaterials, glass and glazing, plastics, mechanicalsystems, special construction, site work,demolition and construction in the public right-ofway, building permittable work in existingbuildings and control of manufactured buildingsand manufactured components, etc., ashistorically addressed in the Massachusetts StateBuilding Code are regulated by 780 CMR.Exception: The design and constructionrequirements of bunkers and magazines for thestorage of explosive materials, flammable/combustible liquids and chemical processsafety, shall default to the specificrequirements of 527 CMR and are notenforceable by Building Officials but rather bythe Head of the Fire Department or his/herdesignee.Note that the IFC and the IMC are not onlybuilding and building permittable systemsdesign and construction documents but alsoinclude fire prevention requirements and thefire prevention requirements of the IFC andIMC are not requirements regulated by780 CMR nor enforceable by BuildingOfficials. For fire prevention requirements donot refer to the IFC or IMC but rather to TheMassachusetts Board of Fire Prevention8/22/08 (Effective 9/1/08)Regulations (527 CMR). If there is conflictbetween 780 CMR and 527 CMR, the morestringent standard shall apply.301.1.2 The ICC International Fire Code (IFC),the ICC International Mechanical Code (IMC)and the Family of Massachusetts SpecializedCodes (refer to 780 CMR, 101.5). 780 CMRcontains design and construction requirements forall USE Group buildings and their buildingpermittable systems and also referencesadditional applicable design and constructionrequirements of the IFC and the IMC for thevarious USE Groups and industrial processeswithin such USE Groups, including H-USES. It isthe intention in referencing the IFC and the IMCthat only the IFC and IMC requirements narrowto Building Code matters (see 780 CMR 301.1.1)are regulated by 780 CMR. Where the IFC andIMC reference requirements related to:architectural access; environmental protection;electrical; elevator; fire prevention (otherwise notspecifically regulated by 527 CMR); gas; orsanitary code requirements, such requirementsare not regulated by 780 CMR nor enforceable byBuilding Officials (Building Officials do enforcearchitectural access requirements set forth in521 CMR). For Specialized Code requirementsdo not refer to the IFC or IMC but rather to theappropriate Specialized Code requirements ofMassachusetts (refer to 780 CMR, 101.5).780 CMR 302.0 CLASSIFICATION302.1 General. Structures or portions of structuresshall be classified with respect to occupancy in oneor more of the groups listed below. Structures withmultiple uses shall be classified according to780 CMR 302.3. Where a structure is proposed fora purpose which is not specifically provided for in780 CMR, such structure shall be classified in thegroup which the occupancy most nearly resembles,according to the fire safety and relative hazardinvolved.1. Assembly (See 780 CMR 303.0): Groups A-1,A-2, A-3, A-4 and A-52. Business (See 780 CMR 304.0): Group B3. Educational (See 780 CMR 305.0): Group E4. Factory and Industrial (See 780 CMR 306.0):Groups F-1 and F-25. High Hazard (See 780 CMR 307.0): GroupsH-1, H-2, H-3, H-4 and H-56. Institutional (See 780 CMR 308.0): Groups I1, I-2, I-3 and I-47. Mercantile (See 780 CMR 309.0): Group M780 CMR - Seventh Edition45

780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDSTHE MASSACHUSETTS STATE BUILDING CODE8. Residential (See 780 CMR 310.0): Groups R1, R-2, R-3 as applicable in 780 CMR 101.2, andR-49. Storage (See 780 CMR 311.0): Groups S-1and S-210. Utility and Miscellaneous (See 780 CMR312.0): Group U302.1.1 Incidental Use Areas. Spaces which areincidental to the main occupancy shall beseparated or protected, or both, in accordance withTable 302.1.1 or the building shall be classified asa mixed occupancy and comply with 780 CMR302.3. Areas that are incidental to the mainoccupancy shall be classified in accordance withthe main occupancy of the portion of the buildingin which the incidental use area is located.Exception: Incidental use areas within andserving a dwelling unit are not required tocomply with 780 CMR 302.0.302.1.1.1 Separation. Where Table 302.1.1requires a fire-resistance-rated separation, theincidental use area shall be separated from theremainder of the building with a fire barrier.Where Table 302.1.1 permits an automatic fireextinguishing system without a fire barrier, theincidental use area shall be separated byconstruction capable of resisting the passage ofsmoke. The partitions shall extend from thefloor to the underside of the fire-resistancerated floor/ceiling assembly or fire-resistancerated roof/ceiling assembly or to the undersideof the floor or roof deck above. Doors shall beself-closing or automatic-closing upondetection of smoke. Doors shall not have airtransfer openings and shall not be undercut inexcess of the clearance permitted in accordancewith NFPA 80.TABLE 302.1.1INCIDENTAL USE AREASROOM OR AREAFurnace room where any pieceof equipment is over 400,000Btu per hour inputRooms with any boiler over 15psi and 10 horsepowerSEPARATION a1 hour or provide automaticfire-extinguishing system1 hour or provide automaticfire-extinguishing system1 hour or provide automaticRefrigerant machinery roomssprinkler system2 hours; or 1 hour andParking garage (Section 406.2) p r o v id e auto matic fire extinguishing systemHydrogen cut-off rooms1 -h o u r fire b a r r ie r s a n dfloor/ceiling assemblies inGroup B, F, H, M , S and Uoccupancies. 2-hour firebarriers and floor/ceilingassemblies in Group A, E, Iand R occupancies.Incinerator rooms2 h o u rs a n d a u to m a t i csprinkler systemPaint shops, not classified as 2 hours; or 1 hour andG ro up H , located in p r o v i d eautomaticoccupancies other than Group fire-extinguishing systemFLaboratories and vocationalshops, not classified as GroupH, located in Group E or I-2occupanciesLaundry rooms over 100 squarefeetStorage rooms over 100 squarefeetGroup I-3 cells equipped withpadded surfacesGroup I-2 waste and linencollection roomsW aste and linen collectionrooms over 100 square feetStationary lead-acid batterysystem s having a liquidcapacity of more than 100gallons used for facilitystandby power, emergencypower or uninterrupted powersupplies1 hour or provide automaticfire-extinguishing system1 hour or provide automaticfire-extinguishing system1 hour or provide automaticfire-extinguishing system1 hour1 hour1 hour or provide automaticfire-extinguishing system1-hour fire barriers andfloor/ceiling assemblies inGroup B, F, H , M, S and Uoccupancies. 2-hour firebarriers and floor/ceilingassemblies in Group A, E, Iand R occupanciesFor SI: 1 square foot 0.0929 m2, 1 pound persquare inch 6.9 kPa, 1 British thermal unit perhour 0.293 watts, 1 horsepower 746 watts, 1gallon 3.785 L.a. Where an automatic fire-extinguishing system isprovided, it need only be provided in the incidentaluse room or area302.2 Accessory Use Areas. A fire barrier shall berequired to separate accessory use areas classified asGroup H in accordance with 780 CMR 302.3.2, andincidental use areas in accordance with 780 CMR302.1.1. Any other accessory use area shall not berequired to be separated by a fire barrier provided theaccessory use area occupies an area not more than10% of the area of the story in which it is locatedand does not exceed the tabular values in Table 503for the allowable height or area for such use.46780 CMR - Seventh Edition8/22/08 (Effective 9/1/08)

780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDSUSE AND OCCUPANCY CLASSIFICATION302.2.1 Assembly Areas. Accessory assemblyareas are not considered separate occupancies ifthe floor area is equal to or less than 750 squarefeet (69.7 m2). Assembly areas that are accessoryto Group E are not considered separateoccupancies. Accessory religious educationalrooms and religious auditoriums with occupantloads of less than 100 are not considered separateoccupancies (also See 780 CMR 303.1 and303.1.1).302.3 Mixed Occupancies. Where a building isoccupied by two or more uses not included in thesame occupancy classification, the building orportion thereof shall comply with 780 CMR 302.3.1and/or 302.3.2.Exceptions:1. Occupancies separated in accordance with780 CMR 508.0.2.Areas of Group H-2, H-3, H-4 or H-5occupancies shall be separated from any otheroccupancy in accordance with 780 CMR 302.3.2.3. Where required by Table 415.3.2, areas ofGroup H-1, H-2 or H-3 occupancy shall be locatedin a separate and detached building or structure.4.Accessory use areas in accordance with780 CMR 302.2.5.Incidental use areas in accordance with780 CMR 302.1.1.302.3.1 Nonseparated Uses. Each portion of thebuilding shall be individually classified as to use.The required type of construction for the buildingshall be determined by applying the height andarea limitations for each of the applicableoccupancies to the entire building. The mostrestrictive type of construction, so determined,shall apply to the entire building. All other coderequirements shall apply to each portion of thebuilding based on the use of that space except that8/22/08 (Effective 9/1/08)the most restrictive applicable provisions of780 CMR 403.0 and 780 CMR 9.00 shall apply tothese nonseparated uses. Fire separations are notrequired between uses, except as required by otherprovisions.302.3.2 Separated Uses. Each portion of thebuilding shall be individually classified as to useand shall be completely separated from adjacentareas by fire barrier walls or horizontal assembliesor both having a fire-resistance rating determinedin accordance with Table 302.3.2 for uses beingseparated. Each fire area shall comply with780 CMR based on the use of that space. Eachfire area shall comply with the height limitationsbased on the use of that space and the type ofconstruction classification. In each story, thebuilding area shall be such that the sum of theratios of the floor area of each use divided by theallowable area for each use shall not exceed one.Exception: Except for Group H and I-2 areas,where the building is equipped throughout withan automatic sprinkler system, installed inaccordance with 780 CMR 903.3.1.1, the fireresistance ratings in Table 302.3.3 shall bereduced by one hour but to not less than 1 hourand to not less than that required for floorconstruction according to the type ofconstruction.302.4 Spaces Used for Different Purposes. Aroom or space that is intended to be occupied atdifferent times for different purposes shall complywith all the requirements that are applicable to eachof the purposes for which the room or space will beoccupied.780 CMR - Seventh Edition47