A single step with a maximum riser height of 7 inches is permitted for buildings with occupancies in Groups F, H, R-2, and R-3 and Groups S and U at outside doors not required to be accessible.The provisions of this chapter control the design, construction, and arrangement of means of egress, or simply put, exit tools that are required to provide an approved means of exit from structures or portions thereof. It is against code to alter a building or structure in a manner that will reduce the number of exits or the capacity of the exits to be any less than is required by this code. All means of exits must be maintained in accordance with the International Fire Code.
The general requirements specified in this section apply to all three elements of the means of exit, or a way out or egress (please note that the words way out, exit, and egress may be used interchangeably and have the same meaning) system, in addition to those specific requirements for the exit access, the exit, and the exit discharge detailed elsewhere in this chapter.
While at the ceiling construction phase keep in mind there must be a minimum of 80 inches for headroom for any walking surface, including walks, corridors, aisles, and passageways. Not more than 50 percent of the ceiling area of the means of exit can be reduced in height by protruding objects; an exception to this is door closers and stoppers. The code states that these cannot reduce headroom to less than 78 inches and you must provide a barrier where the vertical clearance is less than 80 inches high.
The leading edge of any barrier must be located 27 inches (maximum) from the floor. If you have installed a free-standing object that is mounted on a post or pylon, it cannot overhang more than 4 inches where the lowest point of the leading edge is more than 27 inches and less than 80 inches above the walking surface.
If a sign or other obstruction is mounted between posts or pylons and the clear distance between the posts/pylons is greater than 12 inches then the lowest edge of the sign or obstruction must be 27 inches maximum or 80 inches minimum above the finished floor or ground, except that this requirement shall not apply to sloping portions of handrails serving stairs and ramps.
Structural elements, fixtures, or furnishings cannot project horizontally from either side more than 4 inches over any walking surface between the heights of 27 inches and 80 inches above the walking surface (handrails that service stairs and ramps are permitted to protrude 4.5 inches from the wall). Protruding objects will not reduce the minimum clear width of accessible routes.
Note that all walking surfaces of the means of exits must have a slip-resistant surface and be securely attached. This will protect occupants when traveling from rooms to exits. In those places where changes in elevation of less than 12 inches exist in the way of exits, sloped surfaces must be used. If the slope is greater than one side or the other, you must have a ramp installed
CODE UPDATE |
An aisle is an unenclosed exit access component that defines and provides a path of egress travel. |
CODE UPDATE |
A flight is a continuous run of rectangular treads, winders or combination thereof from one landing to another. |
that complies with this chapter. If the difference in elevation is 6 inches or less, the ramp must be equipped with either handrails or floor finish materials that contrast with adjacent floor finish materials. The following is a list of exceptions that pertain to the elevation change:
A single step with a maximum riser height of 7 inches is permitted for buildings with occupancies in Groups F, H, R-2, and R-3 and Groups S and U at outside doors not required to be accessible.
A stair with a single riser or with two risers and a tread is permitted at locations not required to be accessible provided that the risers and threads comply with this chapter, have a minimum tread depth of 13 inches, and at least one handrail that complies with this chapter is provided within 30 inches of the centerline of the normal path of exit travel on the stair.
A step is allowed in aisles serving seating that has a difference in elevation less than 12 inches at locations not required to be accessible provided that the risers and treads comply with this chapter and the aisle has a handrail complying with this chapter.
Any change in elevation in a corridor serving non-ambulatory persons in Group I-2 occupancy must be by means of a ramp or sloped walkway. The path of the exit cannot be interrupted by any building element other than a means of egress component as specified in this chapter. Obstructions cannot be placed in the required width of a means of exit except projections that are permitted by this chapter. The required capacity of a means of exit system cannot be diminished along the path of exit travel. You cannot count elevators, escalators, and moving walks as a component of a required means of egress from any other part of the building, except when elevators are used as an accessible means of egress in accordance with this chapter.
When you are constructing a building, you must always use the number of occupants when determining any means of egress or exit. In areas where occupants from accessory areas exit through a primary space, the calculated occupant load for the primary space must include the total occupant load. Every room or space that is an assembly occupancy must have the occupant load of the room or space posted in a conspicuous place, near the main exit or exit access doorway from the room or space. Posted signs must be of an approved legible permanent design and must be maintained by the owner or authorized agent.
Where exits serve more than one floor, only the occupant load of each floor considered individually must be used in computing the required capacity of the exits at that floor, provided that the exit capacity will not decrease in the direction of exit travel. Where means of egress from floors above and below converge at an intermediate level, the capacity of the means of egress from the point of junction must be less than the sum of the two floors.
The code contains the maximum floor area allowances per occupant. The number of occupants must be computed at the rate of one occupant per unit of area. Where an intended use is not listed, the building official will establish a use based on a listed use that most nearly resembles the intended use. The exception being that where approved by the building official, the actual number of occupants for whom each occupied space, floor, or building is designed, although less than those determined by calculation will be permitted to be used in the determination of the design occupant load.
For areas that have fixed seats and aisles, the occupant load must be determined by the number of fixed seats installed. The occupant load for areas in which fixed seating is not installed, such as waiting areas and wheelchair spaces, must be determined in accordance with this chapter and added to the number of fixed seats. For areas that have fixed seating without dividing arms, the occupant load cannot be less than the number of seats bases on one person for each 18 inches of seating length. The occupant load of seating booths must be based on one person for each 24 inches of booth seat length measured at the backrest of the seating booth.
CODE UPDATE |
Protruding objects shall not reduce the minimum clear width of accessible routes. |
The means of egress, including the exit discharge, must be illuminated at all times in the building space that the egress occupies, except for the following:
Occupancies in Group U
Aisle access ways in Group A
Dwelling and sleeping units in Groups R-1, R-2, and R-3
Sleeping units of Group I occupancies.
The illumination level cannot be less than one foot-candle or 11 lux at the walking surface level except for auditoriums, theaters, concert or opera halls and similar assembly occupancies. The illumination at the walking surface level is allowed to be reduced during performances to not less than 0.2 foot-candle, provided that the required illumination is automatically restored upon activation of a premises’ fire alarm system where such system is provided.
|
This code requires that the total width of means of egress in inches must not be less than the total occupant load served by the means of egress multiplied by the factors in tables found in the code and not less than specified elsewhere in this code. Multiple means of egress much be sized such that the loss of any one means of egress must not reduce the available capacity to less than 50 percent of the required capacity. The maximum capacity required from any story of a building shall be maintained to the termination of the means of egress. |
The power supply for exit illumination must normally be provided by the electrical supply. In the event that the power supply is cut off an emergency electrical system must automatically illuminate the following areas:
Aisles and unenclosed egress stairways in rooms and spaces that require two or more means of exits
Corridors, exit enclosures, and exit passageways in buildings required to have two or more exits
Exterior exit components at other than the level of exit discharge until exit discharge is accomplished for buildings required to have two or more exits
Interior exit discharge elements, as permitted in this chapter, in buildings required to have two or more exits
Exterior landings for exit discharge doorways in buildings required to have two or more exits.
Accessible spaces are to be provided with no less than one means of accessible means of egress. Three exceptions to accessible spaces exits are:
Accessible means of egress are not required in alterations to existing buildings.
|
The emergency power system must provide power for the duration of not less than 90 minutes and has to consist of storage batteries, unit equipment, or an on-site generator. |
One accessible means of egress is required from an accessible mezzanine level in accordance with this chapter.
In assembly spaces with sloped floors, one accessible means of egress is required from a space where the common path of travel of the accessible route for access to the wheelchair spaces meets the requirements in this chapter.
Each required accessible means of egress must be continuous to a public way and has to consist of one or more of the following components:
Accessible routes
Stairways within vertical exit enclosures
Exterior exit stairways
Elevators
Platform lifts
Horizontal exits
Ramps
Areas of refuge.
!Definition alert |
Accessible means of egress: A continuous and unobstructed way of egress travel from any accessible point in a building or facility to a public way. |
These components must comply with the International Building Code book. At least one required accessible means of egress must be an elevator complying with this section, except for buildings that are equipped throughout with an automatic sprinkler system. The elevator is not required on floors provided with a horizontal exit and located at or above the level of exit discharge or if the building provides a ramp that conforms to this chapter.
The use of stairs for an accessible means of exit is common. In order to use stairs in this capacity, the exit stairway has to have a clear width of 48 inches between handrails and must either incorporate an area of refuge within an enlarged floor-level landing or must be accessed from either an area of refuge or a horizontal exit. Please see the following list for exceptions.
Unenclosed exit stairways as permitted by this chapter are allowed to be considered part of an accessible means of egress.
The area of refuge is not required at unenclosed exit stairways as permitted by this chapter in buildings or facilities that are equipped throughout with an automatic sprinkler system.
The clear width of 48 inches between handrails is not required at exit stairways in buildings or facilities equipped throughout with an automatic sprinkler system installed or for exit stairways accessed from a horizontal exit.
Areas of refuge are not required at exit stairways serving open parking garages.
In order to be considered part of an accessible means of egress, an elevator must comply with the emergency operation and signaling device requirements or Section 2.27 of ASME A17.1, and standby power must be provided. The elevator must be accessed from either an area of refuge complying with this chapter or a horizontal exit; elevators are not required to be accessed from an area of refuge or horizontal exit in open parking garages.
Lifts that are used for wheelchairs do not serve as part of an accessible means of egress, except where allowed as part of a required accessible route. If you plan on installing a platform lift on an accessible means of egress, they cannot be installed in a fully enclosed or fire-rated shaft.
In your building structure you must have an area of refuge, which is required by code. This refuge space must be accessible from the space it serves by an easily reached means of an exit or way out. Keep in mind that this accessible space to the exit has to have a maximum travel distance and cannot be more than the travel distance that is permitted for the type of occupancy that you have built. Also, every required area of refuge must have a direct access to an enclosed stairway or an elevator.
You may use an elevator lobby for an area of refuge as well, and it must comply with the code regarding smokeproof enclosures. In regards to any refuge, stairway, or elevator and lobby they all must comply with the code in this chapter. Don’t be fooled into thinking that just by obeying the code to provide refuge areas is enough. There is a size requirement as well.
Each area of refuge must always be large enough to accommodate one wheelchair space of 30 inches by 48 inches for each 200 occupants, based on the occupant load of the area of refuge and areas that are served by these areas. The wheelchair spaces cannot reduce the required means of egress width and access to any of the required wheelchair spaces in an area of refuge can never be obstructed by more than one adjoining wheelchair space.
A separation of each area of refuge by a smoke barrier is mandated. This barrier must comply with the code or a horizontal exit complying with this chapter. Each area of refuge must be designed to minimize the intrusion of smoke, except for those areas which are located within a vertical exit enclosure. Each area of refuge must have a central control point and must be equipped with a two-way communication system.
If the central control point is not constantly attended, the area has to have controlled access to a public telephone. All locations of the central control point must have a stamp of approval by the fire department. Don’t forget that when you choose a two-way communication system that it must have both audible and visible signals. Make sure that in any areas of refuge instructions on the use of the areas (under emergency conditions) are posted with the communications system. All instructions must have the following items included in them:
CODE UPDATE |
Egress doors are normally required to be of the pivoted or side-hinged swinging type. |
CODE UPDATE |
With some exceptions, stair treads and risers are required to be of a uniform shape and size. |
Directions to find other means of egress
Persons able to use the exit stairway must do so as soon as possible, unless they are assisting others.
Information on planned availability of assistance in the use of stairs or supervised operation of elevators and how to ask for such assistance
Directions for the use of the emergency communications system.
Each door that provides access to an area of refuge from an adjacent floor area must be identified by a sign that complies with ICC A117.1; it must clearly state: AREA OF REFUGE and it also has to include the International Symbol of Accessibility. In places that require an illuminated sign, the area of refuge sign must be illuminated.
The above is just one definition of a door. This section has many code rules regarding doors, gates, and turnstiles, all of which are used as a means of exit. Means of doors must be readily distinguishable from the adjacent construction and finishes such that the doors are easily recognizable as doors.
Mirrors or similar reflecting materials will not be used on means of exit doors. Means of exit doors will not be hidden by curtains, drapes, decorations, or similar materials.
The minimum width allowed of each door opening has to be sufficient for the occupant load and has to provide a clear width of not less than 32 inches. If the doorway has swinging doors the clear opening has to be measured between the face of the door and the stop, with the door open 90 degrees. Where this section requires a minimum clear width of 32 inches and a door opening includes two door leaves without a mullion, which is a vertical piece of wood that divides the opening, one leaf must provide a clear opening width of 32 inches.
The maximum width of a swinging door leaf has to be 48 inches nominal. Exit doors in a Group I-2 occupancy used for the movement of beds must have a clear width not less than 41.5 inches. One more thing: the height of all doors cannot be less than 80 inches. Review the following list of exceptions of width and height of doors:
The minimum and maximum width does not apply to door openings that are not part of the required means of egress in Group R-2 and R-3 occupancies.
Door openings to resident sleeping units in Group I-3 occupancies must have a clear width of not less than 28 inches.
Door openings to storage closets less than 10 square feet in area are not limited by the minimum width.
Width of door leafs in revolving doors that comply with this chapter are not limited.
Door openings within a dwelling or sleeping unit cannot be less than 78 inches in height.
Outside door openings in dwellings and sleeping units, other than the required exit door, are not to be less than 76 inches in height.
!Definition alert |
Door, balanced: A door equipped with double-pivoted hardware so designed as to cause a semi counterbalanced swing action when opening. |
In other than Group R-1 occupancies, the minimum widths apply to inside exit doors within a dwelling or sleeping unit that is not required to be an accessible unit, Type A or Type B unit.
Door openings required to be accessible within Type B units must have a minimum clear width of 31.75 inches.
For doors that have the required clear width of less than 34 inches above the ground, there must be no projections. Projections into the clear opening width between 34 inches and 80 inches above the floor or ground cannot exceed 4 inches. Did you know that exit doors must be side-hinged swinging? Read on for exceptions to this rule.
Private garages, office areas, factory and storage areas with an occupant load of 10 or less
Group I-3 occupancies used as a place of detention
Critical or intensive care patient rooms within suites of health care facilities
Doors within or serving a single dwelling unit in Groups R-2 and R-3
In other than Group H occupancies, revolving doors complying with this chapter
In other than Group H occupancies, horizontal sliding doors are permitted as a means of egress
Power-operated doors
Doors serving a bathroom within an individual sleeping unit in Group R-1.
All of these exceptions must comply with their proper chapter or section of the code book. Doors must swing in the direction of exit travel where serving an occupant load of 50 or more persons or a Group H occupancy. The opening force for inside side-swinging door closers cannot go over a 5-pound force. For other side-swinging, sliding, and folding doors, the door latch must release when subjected to a 15-pound force. Plus, the door must be set in motion when faced with a 30-pound force. The door must swing to a full-open position when subjected to a 15-pound force. All forces must be applied to the side with the latch. If you have installed special doors, such as revolving doors, and security grilles they must comply with the following list:
CODE UPDATE |
Exit signs are not required in dayrooms, sleeping rooms, or dormitories in occupancies in Group I-3. |
Each revolving door has to be capable of collapsing into a book fold position with parallel exit paths providing an aggregate width of 36 inches.
A revolving door cannot be located within 10 feet of the foot of or top of stairs or escalators.
A dispersal area must be provided between stairs or escalators and revolving doors.
The revolutions per minute for a revolving door cannot be more than those shown in the code.
Each revolving door must have a side-hinged swinging door which complies with this chapter in the same wall and within 10 feet of the revolving door.
A revolving door that is used as a component of a means of exit must comply with this chapter and meet the following conditions:
Revolving doors cannot be given credit for more than 50 percent of the required exit capacity.
Each revolving door must be credited with no more than a 50-person capacity.
Each revolving door must be capable of being collapsed when a force of no more than 130 pounds is applied within 3 inches of the outer edge of a wing.
If a revolving door is being used as other than a component of a means of egress then the collapsing force of a revolving door not used in this capacity must have a means of egress not more than 180 pounds. An exception to this is a collapsing force in excess of 180 pounds is permitted if the collapsing force is reduced to not more than 130 pounds when at least one of the following conditions is met:
There is a power failure of power is removed to the device holding the door wings in position
There is an actuation of the automatic sprinkler system where this system is provided
There is an actuation of a smoke detection system which is installed to provide coverage within the building which is within 75 feet of the revolving doors
There is an actuation of a manual control switch, in an approved location and clearly defined, which reduces the holding force to below the 130-pound force level.
Floors and landings have to be at the same elevation on each side of a door. Landings must be level, except for outside landings which are allowed to have a slope that does not exceed 0.25 unit vertical in 12 unit horizontal or 2-percent slope. See the list below for exceptions:
Doors serving individual dwelling units in Groups R-2 and R-3 where a door is permitted to open at the top step of an interior flight of stairs provided the door does not swing over the top step, however, screen and storm doors are permitted to swing over stairs or landings
In Group R-3 occupancies not required to be accessible units, Type A or Type B units, the landing at an outside doorway must not be more than 7.75 inches below the top of the threshold, provided that the door, other than an outside storm or screen door, does not swing over the landing.
Variations in elevation due to differences in finish materials, but not more than 0.5 inch
Outside decks, patios, or balconies that are part of Type B dwelling units, have inaccessible surfaces, and are not more than 4 inches below the finished floor level of the adjacent interior space of the living unit.
Door handles, pulls, latches, and locks must be installed 34 inches minimum and 48 inches maximum above the finished floor. Locks used only for security purposes and not used for normal operation are allowed at any height except for access doors or gates in barrier walls and fences that are used to protect pools, spas and hot tubs which are allowed to have operable parts so the latch release on self-latching devices is at 54 inches maximum above the finished floor or ground, but they cannot be self-locking devices that need a key, electronic opener, or integral combination lock.
There are doors in certain occupancies where locks and latches are permissible in places of detention or restraint and in buildings in occupancy Group A having an occupant load of 300 or less, Groups B, F, M, and S, and in places of religious worship.
The main exterior of these doors are allowed to be equipped with key-operated locking devices from the exit side as long as the locking device can be identified as being locked. There also needs to be a sign, visible to all, adjacent to the door that clearly states: This Door To Remain Unlocked When The Building Is Occupied. There is no exception to this rule!
The sign letters are to be 1 inch high on a contrasting background. Anyplace where the doors are used in pairs, automatic flush bolts are allowed to be used, but they need to be approved and only allowed if the door leaf that has the automatic flush bolts has no doorknob or surface-mounted hardware.
|
Doorway landings must have a width of no less than the width of the stairway or the door, whichever is greatest. Doors in a fully open position must not reduce the landing to less than one-half its required width. Landings must have a length measured in the direction of travel of no less than 44 inches. One exception to this code is that the landing length in the direction of travel in Groups R-3 and U and within individual units of Group R-2 does not have to be more than 36 inches. |
Doors that are individual dwelling or sleeping units in Group R occupancies with an occupant load of 10 or less are permitted to be equipped with a night latch, dead bolt, or security chain, but only if they are able to be open from the inside without using a key or tool.
Handrails with a circular cross-section must have an outside diameter of at least 1.25 inches, but no greater than 2 inches or must provide equivalent graspability. If the handrail is not circular, it must have a perimeter dimension of at least 4 inches and not greater than 6.25 inches with a maximum cross-section dimension of 2.25 inches. The maximum radius of edges must be 0.01 inch. Generally speaking, handrail-gripping surfaces must be continuous, without interruption by newel posts or other obstructions.
The code states that the width of stairways cannot be less than 44 inches. There are a few exceptions to this as follows:
Stairways that serve an occupant load of less than 50 must have a width of no less than 36 inches.
Where an incline platform lift or stairway chairlift is installed on stairways that serve occupancies in Group R-3, or within dwelling units in occupancies Group R-2, a clear passage width of no less than 20 inches must be provided. If the seat and platform can be folded when not in use, the distance can be measured from the folded position.
All stairways must have a minimum headroom clearance of 80 inches. This has to be measured vertically from a line connecting the edge of the nosings. The headroom has to be continuous from above the stairway to the point where the line intersects the landing below, one tread depth beyond the bottom riser. Note, however, that spiral stairways, while complying with this section, are allowed to have a 78-inch headroom clearance.
Stair tread depths have a minimum requirement of 11 inches. Riser heights are measured vertically between the leading edges of adjacent treads and the tread depth is to be measured horizontally between the vertical planes of the primary projection of adjacent treads and at a right angle to the tread’s leading edge. Winders also have a minimum tread depth which is 11 inches that are measured at a right angle to the tread’s leading edge at a point 12 inches from the side where the treads are narrower and a minimum tread depth of 10 inches. It’s important for these measurements to be absolutely accurate. Any difference can make the stairways too steep; appear too high or even too long.
Alternating tread devices, spiral stairways, and aisle stairs are a few exceptions, and are discussed later in this chapter. However, in Group R-3 occupancies, within dwelling units in Group R-2 occupancies, and in Group U occupancies that are accessory to a Group R-3 occupancy or accessory to individual dwelling units in Group R-2 occupancies the maximum riser height is 7.75 inches. The maximum winder tread depth at the walk line must be 10 inches and the minimum winder tread depth is 6 inches. A nosing no less than 0.75 inch, but not more than 1.25 inches must be provided on stairways with solid risers where the tread depth is less than 11 inches. These measurements are exact and there are no exceptions. The tolerance between the largest and smallest riser height or between the largest and smallest tread depth must not be more than 0.375 inch in any flight of stairs.
The greatest winder tread depth at the 12-inch walk line within any flight of stairs must not exceed the smallest by more than 0.375 inch measured at a right angle to the tread’s leading edge. Where the bottom or top riser adjoins a sloping public way, walkway, or driveway having an established grade and serving as a landing, the bottom or top riser is permitted to be reduced along the slope to less than 4 inches in height, with the variation in height of the bottom or top riser not to exceed one unit vertical in 12 units horizontal (8-percent slope) of stairway width.
The nosings or leading edges of treads at such non-uniform height risers must have a distinctive marking stripe, different from any other nosing marking provided on the stair flight. The distinctive marking stripe must be visible in descent of the stair and must have a slip-resistant surface. Any marking strip must be at least 1 inch wide, but no wider than 2 inches.
Stairway landings must be found at the top and the bottom of each stairway, and the width of such landing cannot be less than the width of the stairway. Every landing must have a minimum dimension measured in the direction of travel equal to the width of the stairway. This dimension does not need to be more than 48 inches where the stairway has a straight run. Please see the following items of exceptions:
Aisle stairs complying with this chapter
Doors opening onto a landing cannot reduce the landing to less than one-half the required width. When fully open, the door must not project more than 7 inches into a landing.
The stairway walking surface of treads and landings of a stairway cannot be sloped steeper than one unit vertical in 48 units horizontal in any direction. Stairway treads and landing must have a solid surface and finish floor surfaces must be securely attached. The exception is in Groups F, H, and S occupancies, other than areas of parking structures accessible to the public, openings in treads and landings will not be prohibited provided a sphere with a diameter of 1.125 inches cannot pass through the opening.
All outdoor stairways and outdoor approaches to stairways must be designed so that water will not accumulate on walking surfaces. Enclosures under these stairways such as walls and soffits must be protected by one-hour fire-resistance-rated construction or the fire-resistance rating of the stairway enclosure, whichever is greater. Access to the enclosed space cannot be directly from within the stair enclosure, however, spaces under stairways serving and constrained within a single residential dwelling unit in Group R-2 or R-3 are permitted to be protected on the enclosed side with 0.5-inch gypsum board.
|
Wood handrails are permitted for all types of construction. |
There will be no enclosed usable space under exterior exit stairways unless the space is completely enclosed in one-hour fire-resistance-rated construction. The open space under exterior stairways will not be used for any purpose.
A flight of stairs cannot have a vertical rise greater than 12 feet between floor levels or landings, except for aisle stairs that comply with this code. I said earlier that spiral stairways cannot be used as a component in the means of egress. There are a couple of instances in which they are allowed to be used, and they are as follows:
Spiral stairways are permitted to be used as a component in the means of egress only within dwelling units or from a space no more than 250 square feet in area and serving no more than five occupants, or from galleries, catwalks, and gridirons in accordance with code.
When a spiral stairway is allowed, there are provisions that must be followed. A spiral stairway must have a 7.5 inch minimum clear tread depth at a point 12 inches from the narrow edge. The risers must be sufficient to provide headroom of 78 inches minimum, but riser height cannot be more than 9.5 inches and the minimum stairway width must be 26 inches.
Stairways must have handrails on each side and must comply with this chapter. The following list contains the five exceptions for handrails:
Aisle stairs complying with this code provided with a center handrail do not need additional handrails.
Stairways within dwelling units, spiral stairways, and aisle stairs serving seating only on one side are permitted to have a handrail on one side only.
Decks, patios, and walkways that have a single change in elevation where the landing depth on each side of the change of elevation is greater than what is required for a landing do not require handrails.
In Group R-3 occupancies, a change in elevations consisting of a single riser at an entrance or egress door does not require handrails.
Changes in room elevations of only one riser within dwelling and sleeping units in Group R-2 and R-3 occupancies do not require handrails.
If your building or structure has four or more stories in height above grade plane, one stairway must extend to the roof surface, unless the roof has a slope steeper than four units vertical in 12 units horizontal (33-percent slope). In buildings without an occupied roof, access to the roof from the top story must be permitted to be by an alternating tread device.
When you hear the word ramp, many different definitions may come to mind. In this section the definition will be as follows:
The provisions of this section apply to ramps used as a component of a means of egress. Please see the list of exceptions below:
Other than ramps that are part of the accessible routes providing access or ramped aisles within assembly rooms
Curb ramps must comply with ICC A117.1
Vehicle ramps in parking garages for pedestrian exit access do not have to comply with this section when they are not an accessible route serving accessible parking spaces, other required accessible elements, or part of an accessible means of egress.
Ramps that are used as part of a means of egress must have a running slope no steeper than one unit straight up and 12 units across. The slope of the other pedestrian ramps cannot be steeper than one unit straight up in eight units horizontal, except for an aisle ramp in occupancies of Group A.
!Definition alert |
Ramp: A walking surface that has a running slope steeper than one unit vertical in 20 units horizontal with a 5-percent slope. |
Ramps must have landings at the bottom of each ramp, points of turning, entrance, exits, and at doors. The slope of a ramp’s landing cannot be steeper than one unit, vertically, or a 2-percent slope in any direction. Changes in these levels are not permitted.
All exits and exit access doors have to be marked by an approved exit that can be seen from any direction, so whether you are walking from the south or north of the building, the exit sign is readable from both directions. Where you place your exit sign is very important and the sign must be placed in an area so that no point in a corridor is more than 100 feet, or the viewing distance for the sign, from the nearest visible exit area.
Exit signs are not required in rooms or areas that require only one exit or exit access.
Main exterior exit doors or gates that are obviously and clearly identifiable as exits need not have exit signs where approved by a building official.
Exit signs are not required in occupancies in Group U and individual sleeping units or dwelling units in Group R-1, R-2, or R-3.
Exit signs are not required in sleeping areas in occupancies in Group I-3.
In occupancies in Groups A-4 and A-5, exit signs are not required on the seating side of a stadium or theaters or openings into seating areas where exit signs are provided in the concourse that are readily apparent from the stadium or theater within the seating area in an emergency.
Every sign, including directional signs, must have legible letters without decoration. Letters must be at least 6 inches high, and no less than 0.75 inch wide; less than this is against the code. And there is even a rule for spacing between letters which may not be less than 0.375 inch. Larger signs must have letter widths and spacing in proportion to their height.
The code for handrail extensions has changed from the previous code. According to the current International Building Code stair risers have a maximum height requirement of 7 inches and a minimum of 4 inches. What good are stairways and ramps without handrails? According to the 2009 International Building Code a handrail is defined as a horizontal or sloping rail intended for grasping by the hand for guidance or support. Handrails must be sufficiently attached and adequate in strength and be no less than 34 inches, but not more than 38 inches.
Handrail height is to be measured from above the stair tread nosing. When used on ramps handrail height is measured from the surface of the ramp slope. Some handrails have a circular cross-section and must have an outside diameter of at least 1.25 inches, but not greater than 2 inches or must be able to be grasped easily. If the handrail is not circular, it must have a perimeter dimension of at least 4 inches, but not greater than 6.25 inches with a maximum cross-section dimension of 2.25 inches. Any edge has to have a minimum radius of 0.01 inch. Gripping surfaces of all handrails is to be continuous, without interruption by newel posts or any other obstruction. The following are exceptions:
Handrails within dwelling units are permitted to be interrupted by a newel post at a stair landing.
A volute, turnout, or starting ease is allowed on the lowest tread in houses only.
Handrail brackets or balusters that are attached to the bottom surface of the handrail that do not hang over the sides of the handrail within 1.5 inches are not considered obstructions.
There must be a clear space between a handrail and a wall or other surface that must be at least 1.5 inches. Keep handrails, walls, or other surfaces adjacent to the handrail free of any sharp or abrasive elements, as not doing so is a violation of this code. As with handrails, ramps are required to have a minimum space between rails and the wall and must be at least 36 inches. Also please note that projections into the required width of stairways and ramps cannot be more than 4.5 inches at or below the handrail height.
A guard is a building component or a system of building components located at or near the open sides of elevated walking surfaces that minimizes the possibility of a fall from the walking surface to a lower level. Guards must be placed along the sides of stairways, ramps, and landings that are more than 30 inches above the floor or grade below where the glazing does not meet strength requirements. There are places where guards are not required, including:
On the loading side of docks or piers
On the side of stages (from the audience side), and raised platforms, including steps leading up to the stage and raised platforms
At vertical openings in the performance area of stages and platforms
At elevated walking surfaces attached to stages and platforms providing access to and utilization of special lighting or equipment
Along vehicle service pits not accessible to the public
In assemble seating where guards in accordance with this chapter are permitted and provided.
Guards are used as a protective barrier, but the purpose is defeated if the barriers are not of a certain height. According to the code, a guard cannot be less than 42 inches high, and must be measured vertically above the leading edge of the tread, next to the walking surface or beside a seat. However, for those occupancies in Group R-3, and within individual housing units in occupancies in Group R-2, guards whose top rail also serves as a handrail must have a height of no less than 34 and no more than 38 inches, also measured vertically from the leading edge of the stair tread and nose.
The height in assembly seating areas must be in accordance with this chapter. Guards are in play to prevent you, clients, customers, and the people close to you from getting hurt. Therefore, guards must be installed in screen porches and decks where the walking surface is more than 30 inches above the floor or grade below. These decks and screen porches are of the types that are screened in to prevent insect invasion.
Any component of mechanical equipment that requires service, such as appliances, equipment, fans, or roof hatch openings, that are located within 10 feet of a roof edge or open side of a walking surface and the edge or open side is more than 30 inches above the floor or roof require the installation of a guard that prevents the passage of a 21-inch object.
An exit access is the part of the means of egress or exit system that leads from any occupied portion of a building or structure to an exit. This can be an aisle or a hallway or other means of a walkway. Egress or throughway cannot pass through rooms that are of high hazard occupancy unless the adjoining rooms are accessory to the area and in Groups H, S, or F occupancy when the adjoining or intervening rooms or spaces are the same or an occupancy group that is less hazardous.
An exit cannot pass through kitchens, storage rooms, closets, or other spaces that are used for similar purposes. Keep in mind that an exit egress is not allowed to pass through a room that can be locked or lead through bedrooms or bathrooms. Speaking of dwellings, when more than one tenant lives on any one floor of a building or structure, each tenant space, dwelling, or sleeping unit must be provided with access to the required exits in a clear aisle that does not pass through another tenant unit.
CODE UPDATE |
The required width of corridors shall be unobstructed. |
In Group I-2 occupancies, such as hospitals or nursing facilities, rooms or suites must have an exit access door that leads directly to a corridor. The following are exceptions:
Rooms with exits doors that lead or open directly to the outside at the ground level
Patient sleeping rooms are permitted to have one intervening room if that room is not used as an exit access for more than eight patients.
Special nursing suites are allowed to have one intervening room if they allow direct and constant (visual) supervision by nursing personnel.
Any room that is not located in a suite where the travel distance is not greater than 100 feet is allowed to have exit travel.
Other occupancies other than Groups H-1, H-2, and H-3, the common path of egress or exit travel is not allowed to be more than 75 feet, but Groups H-1, H-2, and H-3 cannot have a common path of egress travel of more than 25 feet. In Group B, F, and S occupancies exit travel cannot be more than 100 feet, and that is only if the building is equipped with an automatic sprinkler system. Say your tenant space, which is considered a Group B, S, or U occupancy, has an occupant load of not more than 30 people, the length of a common path travel cannot be more than 100 feet.
If your building or structure is of Group I-3 occupancy, the path of travel is limited to 100 feet. And finally, the length of a common path travel in Group R-2 occupancy cannot be more than 125 feet provided you have installed an automatic sprinkler system throughout. Always remember that any automatic sprinkler systems must be installed in accordance with this code.
!Definition alert |
Aisle: An exit access component that defines and provides a path of egress travel. |
Aisles that serve as part of the exit access in the means of egress or exit system must comply with this next section. Aisles must be provided from all occupied parts of the exit access which contain seats, tables, furnishings, displays, and similar fixtures or equipment. The required width of aisles must be unobstructed. Doors, however, when fully opened, and handrails must not reduce width by more than 7 inches. And, doors in any position must not reduce the required width by more than one-half. Other projections such as trim and similar decorative features are allowed to project into the required width of 1.5 from each side.
For Group M occupancies where seating is located at a table or counter and is adjacent to an aisle or aisle accessway, the measurement must be made to a line of at least 19 inches. This must be measured from the edge of the table or counter. In the case of other side boundaries for aisle or aisle accessways, the clear width must be measured to walls, edges of seating, and tread edges, except that handrail projections are permitted.
If tables or counters have fixed seating, meaning the seats are bolted to the floor, the width of the aisle accessway must be measured from the back of the chair. Table and seating accessways are required to have a minimum of 12 inches of width plus 0.5 inch of width for each additional foot. The exception to this is parts of aisle accessways having a length that is not more than 6 feet and used by no more than four people. Balconies used for egress purposes have to conform to the same requirements as corridors as well.
Requirements for the number of exits and exit access doorways are dependant upon a number of details in regard to occupancy.
All required exits must be located in such a way that makes their use obvious. Both interior exit stairways and ramps must be enclosed with fire barriers or horizontal assemblies that comply with the code book. The fire-resistance rating of no less than two hours is required when the unit is four stories or more, or no less than one hour when the unit is less than four stories. Be sure to include basements in this calculation, but not mezzanines. Although obvious, an exit enclosure cannot be used for any purpose other than a means of egress. The exceptions for this are numerous and include:
In all occupancies, other than Group H and I, and stairway is not required to be enclosed when the stairway serves an occupant load of less than 10 and the stairway complies with either Item 1.1 or 1.2. In all cases however, the maximum number of connecting open stories cannot not be more than two.
– 1.1 The stairway is open to not more than one story above the story at the level of exit discharge; or
– 1.2 The stairway is open to not more than one story below the story at the level of exit discharge.
Exits in buildings of Group A-5 where all portions of the means of egress are essentially open to the outside need not be enclosed.
Stairways that are used and contained in a single residential dwelling or sleeping unit in Group R-1, R-2, or R-3 occupancies are not required to be enclosed.
Stairways that are not a required means of egress element are not always required to be enclosed.
Stairways in open parking structures that serve only the parking structure are not required to be enclosed.
Stairways in Group I-3 occupancies and means of egress stairways are not required to be enclosed.
In groups other than Group H and Group I occupancies, a maximum of 50 percent of egress stairways serving one adjacent floor are not required to be enclosed, provided at least two means of egress are provided from both floors that are using the open stairways. And, any floors that are interconnected cannot be open to other floors.
In groups other than Group H and I occupancies, inside stairway exits that provide service for the first and second stories of a building that has an automatic sprinkler system throughout are not required to be enclosed, but only if there are at least two means of exits. These interconnected floors cannot be open to other stories.
Any penetrations into and any openings through an exit enclosure are not allowed except for required exit doors, equipment, and ductwork that is necessary for independent pressurization, sprinkler piping, standpipes, electrical raceway serving the exit enclosure and terminating at a steel box that is not more than 16 square inches. Such penetrations must be protected. There must not be any penetrations or communication openings, whether protected or not, between adjacent exit enclosures. Equipment and ductwork for exit enclosure ventilation as allowed by this chapter must meet one of the following terms:
All equipment and ductwork has to be located outside of the building and must be directly connected to the exit enclosure by ductwork enclosed in construction as required by shafts.
Where the equipment and ductwork is located within the exit enclosure, the intake air must be taken directly from the outdoors and the exhaust air must be discharged directly to the outdoors, or the air must be conveyed through ducts enclosed in construction as required by shafts.
Where equipment and ductwork is located within the building, this equipment and ductwork must be separated from the rest of the building, including other mechanical equipment, with construction as required for shafts.
In each case, openings into the fire-resistance-rated construction must be limited to those that are needed for maintenance and operation and must be protected by opening protectives for shaft enclosures. And all exit enclosure ventilation systems must be independent of other building ventilation systems.
The outside walls of an exit enclosure must comply with the requirements for exterior walls. In cases where non-rated walls or unprotected openings enclose the outside of the stairway and the walls or openings are exposed by other parts of the building at an angle of less than 180 degrees, the outside building walls within 10 feet horizontally of a non-rated wall or unprotected opening must have a fire-resistance rating of no less than one hour. And as a reminder, openings within inside walls have to be protected by opening protectives that have a fire protection rating of no less than ¾ hour. This type of construction is to extend vertically—from the ground to a point that is 10 feet—above the uppermost landing of the stairway or to the roof line, but make sure that is the lowest level.
CODE UPDATE |
Exit passageways shall terminate at an exit discharge or a public way. |
All floor landings in every inside exit enclosure that connects more than three stories must have a sign. These signs must identify the floor level and the direction to the exit of that stairway. It must also include the availability of the roof access from the stairway for the fire department, and is to be located 5 feet above the floor landing in such a position that is visible when the doors are in the open and closed positions.
A smokeproof enclosure or pressurized stairway must exit into a public space or into an exit passageway, yard, or open space. Any of these must have direct access to a public area. An exit passageway must have no other openings and be separated from the remainder of the building by two-hour fire-resistance-rated construction. The following is a list of exceptions:
Openings in the exit passageway that serves a smokeproof enclosure are allowed where the exit passageway is protected and pressurized in the same manner as the smokeproof enclosure, and openings are protected as required for access from other floors.
Openings in the exit passageway serving a pressurized stairway are permitted where the exit passageway is protected and pressurized in the same manner as the pressurized stairway.
A smokeproof enclosure or pressurized stairway must be allowed to pass through areas on the level of discharge or vestibules as allowed by this chapter.
The access to this stairway must be through an entrance hall or an open balcony, unless there is a pressurized stairway.
A horizontal exit cannot serve as the only exit from a portion of a building. In buildings where two or more exits are required, not more than one-half of the total number of exits can be horizontal exits. However, if your building is of Group I-2 occupancy, horizontal exits are permitted to make up two-thirds of the required exits.
In Group I-3 occupancies, horizontal exits are allowed to make up 100 percent of the exits required. There must at least 6 square feet of accessible space per occupant on each side of the exit for the total number of people in adjoining compartments. Horizontal exits that connect separation of buildings or refuge areas must provide a fire wall or a fire barrier; both complying with the code and having a fire-resistance rating of no less two hours. Such exit separation must extend vertically through all levels of the building unless the floor assemblies have a fire-resistance rating of no less than two hours with all openings having a protective element. The exception being that a fire-resistance rating is not required at horizontal exits between a building area and an above-grade pedestrian walkway. The walkway has to provide a distance of more than 20 feet and must comply with Special Construction.
!Definition alert |
Horizontal exits: A path of egress travel from one building to an area in another building on approximately the same level, or a path of egress travel through or around a wall or partition to an area on approximately the same level in the same building, which affords safety from fire and smoke from the area of incidence. |
Horizontal exits that contain a refuge area must be a space occupied by the same tenant or public area and each refuge area has to be big enough to accommodate the original occupant load plus any extra people from the adjoining compartment. The anticipated occupant load from the adjoining compartment is based on the capacity of the horizontal exit doors that enter the refuge area. The net floor area allowable per occupancies must be as follows for the indicated occupancies:
Six square feet per occupant for occupancies in Group I-3
Fifteen square feet per occupant for ambulatory occupancies and 30 square feet per occupant in non-ambulatory occupancies in Group I-2.
If a building or structure includes outside exit ramps and stairways that are used as part of a required means of door or way of exit, pay close attention to this section as it pertains to such ramps and stairways. If your building or structure is of Group I-2 occupancy, you may not use exterior ramps and stairways as an element of a means of exit.
All exterior exit ramps and stairways must have at least one open side and have a minimum of 35 square feet of total open area bordering each floor level and the level of each intermediate landing. Take note that the required open area must be located on less than 42 inches above the bordering floor or landing level.
These types of ramps and stairways have to be separated from the inside of the building. Remember, any opening is limited to those necessary for exit from spaces that are normally occupied. However, there are several exceptions to this listed below:
Separation from the interior of the building is not required for occupancies, other than those in Group R-1 or R-2, in buildings that are no more than two stories above grade plane where the level of exit discharge is the first story above grade plane.
Separation from the interior of the building is not required where the exterior ramp or stairway is served by an exterior ramp and/or balcony that connects two remote outside stairways or other approved exits with a perimeter that is no less than 50 percent open. For the opening to be considered open, it must be a minimum of 50 percent of the height of the enclosing wall, with the top of the openings less than 7 feet above the top of the balcony.
Separation from the inside of the building is not required for an inside ramp or stairway located in a building or structure that is allowed to have unenclosed inside stairways in accordance with the chapter.
Separation from the inside of the building is not required for exterior ramps or stairways connected to open-ended corridors, provided that these items are met: the building, which includes corridors and ramps and/or stairs, must be thoroughly equipped with an automatic sprinkler system. The open-ended corridors are connected on each end to an outside exit ramp or stairway and comply with this chapter.
At any location in an open-ended corridor where a change of direction exceeds 45 degrees, a clear opening of no less than 35 square feet or an outside ramp or stairway is provided. If/when clear openings are provided, they must be located so the accumulation of smoke or toxic gases is minimized.
Basements and sleeping rooms that are located below the fourth story above grade plane must have at least one outside emergency escape and rescue opening. If a basement contains one or more bedrooms, emergency egress and openings are required for each bedroom, but are not required in adjoining areas of a basement. Exceptions include the following:
Occupancies other than Group R-3 equipped throughout with an approved automatic sprinkler system.
Occupancies other than Group R-3 that have rooms used for sleeping and have a door that leads to a fire-resistance-rated corridor that has access to two remote exits in opposite directions.
The emergency escape and rescue opening is permitted to open onto a balcony, provided the balcony provides access to an exit and the dwelling or sleeping unit has an exit that does not open to an atrium.
Basements that have a ceiling height of less than 80 inches or basements without habitable space and having no more than 200 square feet in floor area are not required to have an emergency escape and rescue windows.
High-rise buildings with exceptions.
All emergency escape and rescue openings must have a minimum net clear opening of 5.7 square feet, except for grade-floor openings, which must be at least 5 square feet, and both requiring a minimum height of 24 inches and width of 20 inches. The maximum height from the floor in all cases is to be no greater than 44 inches measured from the floor. Keep in mind that all the emergency openings do not mean a thing if they do not work right or cannot be opened from the inside. You can place bars, grilles, or grates over the escape, but they must be removable from the inside without the use of any tool or key. If you choose to install any of the above on an emergency escape you must also have smoke alarms installed as well.
In conclusion of this chapter, it is important that you realize that these provisions are in play for a number of reasons, with safety being one of the most important. As with any chapter of this book, any questions can be addressed to your local code office or building inspector for clarity.
