780 CMR 10.00 MEANS OF EGRESS - Mass.gov - Free Download PDF

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780 CMR 10.00MEANS OF EGRESS780 CMR 1001.0 ADMINISTRATION1001.1 General. Buildings or portions thereof shallbe provided with a means of egress system asrequired by 780 CMR 10.00. The provisions of780 CMR 10.00 shall control the design,construction and arrangement of means of egresscomponents required to provide an approved meansof egress from structures and portions thereof.Note: also refer to 521 CMR (ArchitecturalAccess Rules and Regulations) which will/mayhave impact on ingress/egress design andconstruction.1001.2 Minimum Requirements. It shall beunlawful to alter a building or structure in a mannerthat will reduce the number of exits or the capacityof the means of egress to less than required by780 CMR.1001.3 Maintenance-general. Means of egressshall be maintained to assure that all requiredegress elements and all required lighting andsignage conform to the applicable requirements of780 CMR.1001.3.1 Obstructions. It shall be unlawful toobstruct, or reduce in any manner, the clearwidth of any doorway, hallway, passageway orother means of egress required by the provisionsof 780 CMR.1001.3.2 Maintenance of Exterior Stairs andFire Escapes. All exterior stairways and fireescapes shall be kept free of snow and ice.Exterior stairways and fire escapes constructedof materials requiring the application of weatherprotecting products, shall have these productsapplied in an approved manner and shall beapplied as often as necessary to maintain thestairways and fire escapes in safe condition.Where corrodible structural parts of suchstairways and fire escapes tie directly into thebuilding structural system, all joints shall besealed, as necessary, to prevent water fromdamaging or corroding structural elements.1001.3.3 Testing and Certification. All exteriorbridges, steel or wooden stairways, fire escapesand egress balconies shall be examined and/ortested, and certified for structural adequacy andsafety every five years, by a Massachusettsregistered professional engineer, or othersqualified and acceptable to the building official;said engineer or others shall then submit anaffidavit to the building official.780 CMR 1002.0 DEFINITIONS1002.1 Definitions. The following words and terms8/22/08 (Effective 9/1/08)shall, for the purposes of 780 CMR 10.00 and asused elsewhere in 780 CMR, have the meaningsshown in 780 CMR 1002.1.ACCESSIBLE MEANS OF EGRESS.Acontinuous and unobstructed way of egress travelfrom any point in a building or facility that providesan accessible route to an area of refuge, a horizontalexit or a public way.AISLE ACCESSWAY. That portion of an exitaccess that leads to an aisle.ALTERNATING TREAD DEVICE. A devicethat has a series of steps between 50 and 70 degrees(0.87 and 1.22 rad) from horizontal, usually attachedto a center support rail in an alternating manner sothat the user does not have both feet on the samelevel at the same time.AREA OF REFUGE. An area where personsunable to use stairways can remain temporarily toawait instructions or assistance during emergencyevacuation.BLEACHERS. Tiered seating facilities.COMMON PATH OF EGRESS TRAVEL. Thatportion of exit access which the occupants arerequired to traverse before two separate and distinctpaths of egress travel to two exits are available.Paths that merge are common paths of travel.Common paths of egress travel shall be includedwithin the permitted travel distance.CORRIDOR. An enclosed exit access componentthat defines and provides a path of egress travel to anexit.DOOR, BALANCED. A door equipped withdouble-pivoted hardware so designed as to cause asemi counterbalanced swing action when opening.EGRESS COURT. A court or yard which providesaccess to a public way for one or more exits.EMERGENCY ESCAPE AND RESCUEOPENING. An operable window, door or othersimilar device that provides for a means of escapeand access for rescue in the event of an emergency.EXIT. That portion of a means of egress systemwhich is separated from other interior spaces of abuilding or structure by fire-resistance-ratedconstruction and opening protectives as required toprovide a protected path of egress travel between theexit access and the exit discharge. Exits includeexterior exit doors at ground level, exit enclosures,exit passageways, exterior exit stairs, exterior exitramps and horizontal exits.780 CMR - Seventh Edition259

780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDSTHE MASSACHUSETTS STATE BUILDING CODEEXIT, HORIZONTAL. A path of egress travelfrom one building to an area in another building onapproximately the same level, or a path of egresstravel through or around a wall or partition to an areaon approximately the same level in the samebuilding, which affords safety from fire and smokefrom the area of incidence and areas communicatingtherewith.EXIT ACCESS. That portion of a means of egresssystem that leads from any occupied portion of abuilding or structure to an exit.EXIT DISCHARGE. That portion of a means ofegress system between the termination of an exit anda public way.EXIT DISCHARGE, LEVEL OF. The horizontalplane located at the point at which an exit terminatesand an exit discharge begins.EXIT ENCLOSURE. An exit component that isseparated from other interior spaces of a building orstructure by fire-resistance-rated construction andopening protectives, and provides for a protectedpath of egress travel in a vertical or horizontaldirection to the exit discharge or the public way.EXIT PASSAGEWAY. An exit component that isseparated from all other interior spaces of a buildingor structure by fire-resistance-rated construction andopening protectives, and provides for a protectedpath of egress travel in a horizontal direction to theexit discharge or the public way.FIRE EXIT HARDWARE. Panic hardware that islisted for use on fire door assemblies.FLOOR AREA, GROSS. The floor area within theinside perimeter of the exterior walls of the buildingunder consideration, exclusive of vent shafts andcourts, without deduction for corridors, stairways,closets, the thickness of interior walls, columns orother features. The floor area of a building, orportion thereof, not provided with surroundingexterior walls shall be the usable area under thehorizontal projection of the roof or floor above. Thegross floor area shall not include shafts with noopenings or interior courts.FLOOR AREA, NET. The actual occupied areanot including unoccupied accessory areas such ascorridors, stairways, toilet rooms, mechanical roomsand closets.FOLDING AND TELESCOPIC SEATING.Tiered seating facilities having an overall shape andsize that are capable of being reduced for purposes ofmoving or storing.GRANDSTAND. Tiered seating facilities.GUARD. A building component or a system ofbuilding components located at or near the opensides of elevated walking surfaces that minimizes thepossibility of a fall from the walking surface to a260lower level.HANDRAIL. A horizontal or sloping rail intendedfor grasping by the hand for guidance or support.MEANS OF EGRESS.A continuous andunobstructed path of vertical and horizontal egresstravel from any occupied portion of a building orstructure to a public way. A means of egressconsists of three separate and distinct parts: the exitaccess, the exit and the exit discharge.NOSING. The leading edge of treads of stairs andof landings at the top of stairway flights.OCCUPANT LOAD. The number of persons forwhich the means of egress of a building or portionthereof is designed.PANIC HARDWARE. A door-latching assemblyincorporating a device that releases the latch uponthe application of a force in the direction of egresstravel.PUBLIC WAY. A street, alley or other parcel ofland open to the outside air leading to a street, thathas been deeded, dedicated or otherwise permanentlyappropriated to the public for public use and whichhas a clear width and height of not less than ten feet(3048 mm).RAMP. A walking surface that has a running slopesteeper than one unit vertical in 20 units horizontal(5% slope).SCISSOR STAIR. Two interlocking stairwaysproviding two separate paths of egress located withinone stairwell enclosure.SMOKE-PROTECTED ASSEMBLY SEATING.Seating served by means of egress that is not subjectto smoke accumulation within or under a structure.STAIR. A change in elevation, consisting of one ormore risers.STAIRWAY. One or more flights of stairs, eitherexterior or interior, with the necessary landings andplatforms connecting them, to form a continuous anduninterrupted passage from one level to another.STAIRWAY, EXTERIOR. A stairway that is openon at least one side, except for required structuralcolumns, beams, handrails and guards.Theadjoining open areas shall be either yards, courts orpublic ways. The other sides of the exterior stairwayneed not be open.STAIRWAY, INTERIOR. A stairway not meetingthe definition of an exterior stairway.STAIRWAY, SPIRAL. A stairway having a closedcircular form in its plan view with uniform sectionshaped treads attached to and radiating from aminimum-diameter supporting column.WINDER. A tread with nonparallel edges.780 CMR - Seventh Edition8/22/08 (Effective 9/1/08)

780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDSMEANS OF EGRESS780 CMR 1003.0 GENERAL MEANSOF EGRESS1003.1 Applicability. The general requirementsspecified in 780 CMR 1003.0 through 1012.0 shallapply to all three elements of the means of egresssystem, in addition to those specific requirements forthe exit access, the exit and the exit dischargedetailed elsewhere in 780 CMR 10.00.1003.2 Ceiling height. The means of egress shallhave a ceiling height of not less than seven feet(2134 mm).Exceptions:1. Sloped ceilings in accordance with 780 CMR1208.2.2. Ceilings of dwelling units and sleeping unitswithin residential occupancies in accordance with780 CMR 1208.2.3. Allowable projections in accordance with780 CMR 1003.3.4. Stair headroom in accordance with 780 CMR1009.2.5. Door height in accordance with 780 CMR1008.1.1.1003.3 Protruding Objects. Protruding objectsshall comply with the requirements of 780 CMR1003.3.1 through 1003.3.4.1003.3.1 Headroom. Protruding objects arepermitted to extend below the minimum ceilingheight required by 780 CMR 1003.2 provided aminimum headroom of 80 inches (2032 mm) shallbe provided for any walking surface, includingwalks, corridors, aisles and passageways. Notmore than 50% of the ceiling area of a means ofegress shall be reduced in height by protrudingobjects.Exception: Door closers and stops shall notreduce headroom to less than 78 inches (1981mm).A barrier shall be provided where the verticalclearance is less than 80 inches (2032 mm) high.The leading edge of such a barrier shall be located27 inches (686 mm) maximum above the floor.1003.3.2 Free-standing Objects. A free-standingobject mounted on a post or pylon shall notoverhang that post or pylon more than 12 inches(305 mm) where the lowest point of the leadingedge is more than 27 inches (686 mm) and lessthan 80 inches (2032 mm) above the walkingsurface. Where a sign or other obstruction ismounted between posts or pylons and the cleardistance between the posts or pylons is greaterthan 12 inches (305 mm), the lowest edge of suchsign or obstruction shall be 27 inches (685 mm)maximum or 80 inches (2030 mm) minimumabove the finish floor or ground.Exception. This requirement shall not apply tosloping portions of handrails serving stairs and8/22/08 (Effective 9/1/08)ramps.1003.3.3 Horizontal Projections. Structuralelements, fixtures or furnishings shall not projecthorizontally from either side more than 4 inches(102 mm) over any walking surface between theheights of 27 inches (686 mm) and 80 inches(2032 mm) above the walking surface.Exception: Handrails serving stairs and rampsare permitted to protrude 4.5 inches (114 mm)from the wall.1003.3.4 Clear Width. Protruding objects shallnot reduce the minimum clear width of accessibleroutes as required in 780 CMR 1104.1003.4 Floor Surface. Walking surfaces of themeans of egress shall have a slip-resistant surfaceand be securely attached.1003.5 Elevation Change. Where changes inelevation of less than 12 inches (305 mm) exist inthe means of egress, sloped surfaces shall be used.Where the slope is greater than one unit vertical in20 units horizontal (5% slope), ramps complyingwith 780 CMR 1010.0 shall be used. Where thedifference in elevation is six inches (152 mm) orless, the ramp shall be equipped with eitherhandrails or floor finish materials that contrastwith adjacent floor finish materials.Exceptions:1. A single step with a maximum riser heightof seven inches (178 mm) is permitted forbuildings with occupancies in Groups F, H, R2 and R-3 as applicable in 780 CMR 101.2, andGroups S and U at exterior doors not requiredto be accessible by 780 CMR 11.00.2. A stair with a single riser or with two risersand a tread is permitted at locations notrequired to be accessible by 780 CMR 11.00,provided that the risers and treads comply with780 CMR 1009.3, the minimum depth of thetread is 13 inches (330 mm) and at least onehandrail complying with 780 CMR 1009.11 isprovided within 30 inches (762 mm) of thecenterline of the normal path of egress travelon the stair.3.An aisle serving seating that has adifference in elevation less than 12 inches (305mm) is permitted at locations not required to beaccessible by 780 CMR 11, provided that therisers and treads comply with 780 CMR1024.11 and the aisle is provided with ahandrail complying with 780 CMR 1024.13.Any change in elevation in a corridorserving non ambulatory persons in a Group I-2occupancy shall be by means of a ramp orsloped walkway.1003.6 Means of Egress Continuity. The path ofegress travel along a means of egress shall not beinterrupted by any building element other than ameans of egress component as specified in 780 CMR780 CMR - Seventh Edition261

780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDSTHE MASSACHUSETTS STATE BUILDING CODE10.00. Obstructions shall not be placed in therequired width of a means of egress exceptprojections permitted by 780 CMR 10.00. Therequired capacity of a means of egress system shallnot be diminished along the path of egress travel.1003.7 Elevators, Escalators and Moving Walks.Elevators, escalators and moving walks shall not beused as a component of a required means of egressfrom any other part of the building.Exception. Elevators used as an accessible meansof egress in accordance with 780 CMR 1007.4.780 CMR 1004.0 OCCUPANT LOAD1004.1 Design Occupant Load. In determiningmeans of egress requirements, the number ofoccupants for whom means of egress facilities shallbe provided shall be established by the largestnumber computed in accordance with 780 CMR1004.1.1 through 1004.1.3.Exception. For A-2nc uses also note theprescriptive egress requirements of 780 CMR1024.0 and 780 CMR 3403.0.1004.1.1 Actual Number. The actual number ofoccupants for whom each occupied space, floor orbuilding is designed.1004.1.2 Number by Table 1004.1.2. Thenumber of occupants computed at the rate of oneoccupant per unit of area as prescribed in Table1004.1.2.TABLE 1004.1.2 MAXIMUM FLOOR AREAALLOWANCES PER OCCUPANTOCCUPANCYFLOOR AREA IN SQ.FT. PER OCCUPANT300 gross500 grossAgricultural buildingAircraft hangarsAirport terminalBaggage claim20 grossBaggage handling300 grossConcourse100 grossW aiting areas15 grossAssembly11 grossGaming floors (keno, slots, etc.)Assembly with fixed seatsSee 780 CMR 1003.2.2.9Assembly without fixed seats7 netConcentrated (chairs only— not5 netfixed) Standing space15 netUnconcentrated (tables and chairs)For A-2nc uses also note the prescriptive egress requirements of 780CM R 1024 and 780 CMR 3400.3.Bowling centers, allow five personsfor each lane including 15 feet of7 netrunway, and for additional areasBusiness areas100 grossCourtrooms - other than fixed seating40 netareasDormitories50 grossEducationalClassroom area20 netShops and other vocational room50 netareas262OCCUPANCYExercise roomsH-5 Fabrication and manufacturingareasIndustrial areasInstitutional areasInpatient treatment areasOutpatient areasSleeping areasKitchens, commercialLibraryReading roomsStack areaLocker roomsMercantileAreas on other floorsBasement and grade floor areasStorage, stock, shipping areasParking garagesResidentialSkating rinks, swimming poolsRink and poolDecksStages and platformsAccessory storage areas, mechanicalequipment roomW arehousesFLOOR AREA IN SQ.FT. PER OCCUPANT50 gross200 gross100 gross240100120200grossgrossgrossgross50 net100 gross50 gross60 gross30 gross300 gross200 gross200 gross50 gross15 gross15 net300 gross500 grossFor SI: 1 square foot - 0.0929 m21004.1.3 Number by Combination. Whereoccupants from accessory spaces egress through aprimary area, the calculated occupant load for theprimary space shall include the total occupant loadof the primary space plus the number of occupantsegressing through it from the accessory space.1004.2 Increased Occupant Load. The occupantload permitted in any building or portion thereof ispermitted to be increased from that numberestablished for the occupancies in Table 1004.1.2provided that all other requirements of the code arealso met based on such modified number and theoccupant load shall not exceed one occupant per 5square feet (0.47 m2) of occupiable floor space.Where required by the building official, an approvedaisle, seating or fixed equipment diagramsubstantiating any increase in occupant load shall besubmitted. Where required by the building official,such diagram shall be posted.1004.3 Posting of Occupant Load. Every room orspace that is an assembly occupancy shall have theoccupant load of the room or space posted in aconspicuous place, near the main exit or exit accessdoorway from the room or space. Posted signs shallbe of an approved legible permanent design and shallbe maintained by the owner or authorized agent.1004.4 Exiting from Multiple Levels. Where exitsserve more than one floor, only the occupant load ofeach floor considered individually shall be used incomputing the required capacity of the exits at thatfloor, provided that the exit capacity shall notdecrease in the direction of egress travel.1004.5 Egress Convergence. Where means ofegress from floors above and below converge at an780 CMR - Seventh Edition8/22/08 (Effective 9/1/08)

780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDSMEANS OF EGRESSintermediate level, the capacity of the means ofegress from the point of convergence shall not beless than the sum of the two floors.1004.6 Mezzanine Levels. The occupant load of amezzanine level with egress onto a room or areabelow shall be added to that room or area’s occupantload, and the capacity of the exits shall be designedfor the total occupant load thus established.1004.7 Fixed Seating. For areas having fixed seatsand aisles, the occupant load shall be determined bythe number of fixed seats installed therein.For areas having fixed seating without dividingarms, the occupant load shall not be less than thenumber of seats based on one person for each 18inches (457 mm) of seating length.The occupant load of seating booths shall be basedon one person for each 24 inches (610 mm) of boothseat length measured at the backrest of the seatingbooth.1004.8 Outdoor Areas. Yards, patios, courts andsimilar outdoor areas accessible to and usable by thebuilding occupants shall be provided with means ofegress as required by 780 CMR 10.00. The occupantload of such outdoor areas shall be assigned by thebuilding official in accordance with the anticipateduse. Where outdoor areas are to be used by personsin addition to the occupants of the building, and thepath of egress travel from the outdoor areas passesthrough the building, means of egress requirementsfor the building shall be based on the sum of theoccupant loads of the building plus the outdoorareas.Exceptions:1. Outdoor areas used exclusively for service ofthe building need only have one means of egress.2. Both outdoor areas associated with Group R-3and individual dwelling units of Group R-2, asappl

The actual occupied area not including unoccupied accessory areas such as cor ri do rs , sta ir wa ys, toi le t r oo ms, me cha nic al r oo ms and closets. FOLDING AND TELESCOPIC SEATING. Tiered seating STAfacilities having an over all shape a nd siz e that ar e ca pable of being reduc ed for purposes of moving or storing. GRANDSTAND. Tiered seating facilities. GUARD. A building component or a ...