3Tragedies that created and developed building codes. One of the many tragic fires that shaped the way buildings were design:The Triangle Shirtwaist FireAndIroquois Theater FireT.O
4THE TRIANGLE SHIRTWAIST FIRE New York City, March 25, 1911 -The Triangle Waist Company factory occupied the eighth, ninth, and tenth floors of the 10-story Asch Building on the northwest corner of Greene Street and Washington Place.-cause of the fire was the disposal of a match or cigarette in the scrap bin-A bookkeeper on the eighth floor was able to warn employees on the tenth floor via telephone, but there was no audible alarm and no way to contact staff on the ninth floor. first warning of the fire on the ninth floor arrived at the same time as the fire itself.-The floors had a number of exits, including two freight elevators, a fire escape, and stairways down to Greene Street and Washington Place, but flames prevented workers from descending the Greene Street stairway, and the door to the Washington Place stairway was locked to prevent theft by the workersDozens of employees escaped the fire by going up the Greene Street stairway to the roof and 62 people jumped. Other survivors were able to jam themselves into the elevators while they continued to operate.Crowds were onto a single exterior fire escape, It was a flimsy and poorly anchored iron structure and It soon twisted and collapsed from the heat and overload, killing about 20 victims nearly 100’ to the street.The fire resulted in 146 deathsT.O
5Stairways NYC Building Code require 2 means of egress. Egress extend from floor to ceiling to lead everyone to the closest exit discharge.T.O
9IlluminationLights are required to inform and show people where the nearest exists are.T. O
10ELEVATORS AND ESCALATORS ARE NOT COMPONANTS REQUIRED MEANS OF EGRESS IN ANY BUILDING
11Iroquois Theater Fire Chicago, Illinois 1903 During a second act of a play Fire, smoke, and heat spread quickly through the theater.The North exit doors were blocked by a curtain.When the guests eventually found the door, they were discouraged by an unfamiliar locking device.The dead end corridors and obstructed exits caused panic, pushing, jumping.The fire killed 602 people which is why The Iroquois Theater Fire is now known as the deadliest theater fire and single building fire in the history of the United States.CODE CHANGES-This fire created federal and state standards for exiting pathways, exit doors, exit signs and markings, maximum seating, and the use of the panic bar.M.B.
12Exit Passageway - serves as exit in mean of egress Should be more then 44 inches in case of more then 50 occupants and not less then 36 inches in case of less then 50 occupants.Should have walls, floors and ceiling not less then 1 hour rating.Openings should be limited to those only necessary for exits.M.B.
13Horizontal exits- can serve as additional exits where there is at least two or more exits Can be used as separation between buildings however the minimum fire rating should be two hours and air transfer openings should be applied.Fire doors or automatic doors should be activated by smoke detectors.M.B.
14Exit discharge - serves as exit that leads directly to the exterior of a building Should provide direct access to a grade.The capacity should not be less then the capacity of all other exits in the building.Should provide a safe access to a public way.M.B.
15Main exitsShould be provided in each level of a building used for assembly with load greater then 300 people in addition to other means of egress.Should have capacity of at least half of the total occupant load of each level.Balconies and galleries- having seating capacity of at least 50 people should have minimum of two exits from each side.Travel Distance - exits should be located with maximum of 250 feet between then in sprinkled buildingM.B.
16Marking and symbols- should be provided in all types of buildings except residential in case of private housesShould be in interior exit stairways, exit ramps, exit passageway and in the edges of steps and landings.Should be provided by all the doors that occupants should pass through.Exit symbols should be placed in consistent and uniformed way and should be at least 4 inches.Exterior exit stairway and ramps should be provided and have minimum separation distance of 10 feet.M.B.
17Assembly main exit.In a building, room or space used for assembly purposes that has an occupant load of greater than 300 and is provided with a main exit, the main exit shall be of sufficient width to accommodate not less than one-half of the occupant load, but such width shall not be less than the total required width of all means of egress leading to the exit. Where the building is classified as a Group A occupancy, the main exit shall front on at least one street or an unoccupied space of not less than 10 feet (3048 mm) in width that adjoins a street or public way. ____________________________________________A.P.
18Widths of means of egress for assemblies Assemblies without smoke protection.1. At least 0.3 inch (7.6 mm) of width for each occupant served shall be provided on stairs having riser heights 7 inches (178 mm) or less and tread depths 11 inches (279 mm) or greater, measured horizontally between tread nosings.2. At least inch (0.127 mm) of additional stair width for each occupant shall be provided for each inch (2.5 mm) of riser height above 7 inches (178 mm).3. Where egress requires stair descent, at least inch (1.9 mm) of additional width for each occupant shall be provided on those portions of stair width having no handrail within a horizontal distance of 30 inches (762 mm).Width of means of egress for smoke-protected assembly.___________________________________________________________________A.P.
19Exit access travel distance Exits and aisles shall be so located that the travel distance to an exit door shall not be greater than 200 feet ( mm) measured along the line of travel in nonsprinklered buildings. Travel distance shall not be more than 250 feet ( mm) in sprinklered buildings. Where aisles are provided for seating, the distance shall be measured along the aisles and aisle accessway without travel over or on the seats. Exceptions:-Smoke-protected assembly seating: The travel distance from each seat to the nearest entrance to a vomitory or concourse shall not exceed 200 feet ( mm). The travel distance from the entrance to the vomitory or concourse to a stair, ramp or walk on the exterior of the building shall not exceed 200 feet ( mm).Exit access travel distanceA.P.
22DoorsSize of doors. The minimum width of each door opening shall be sufficient for the occupant load thereof and shall provide a clear width of 32 inches (813 mm). Clear openings of doorways with swinging doors shall be measured between the face of the door and the stop, with the door open 90 degrees (1.57 rad). Where this section requires a minimum clear width of 32 inches (813 mm) and a door opening includes two door leaves without a mullion, one leaf shall provide a clear opening width of 32 inches (813 mm). The maximum width of a swinging door leaf shall be 48 inches (1219 mm) nominal. Means of egress doors in a Group I-2 occupancy used for the movement of beds shall provide a clear width not less than 411/2 inches (1054 mm). The height of door openings shall not be less than 80 inches (2032 mm).Door arrangement. Space between two doors in a series shall be 48 inches (1219 mm) minimum plus the width of a door swinging into the space. Doors in a series shall swing either in the same direction or away from the space between the doors.A.P.
23HANDRAILSHandrail height, measured above stair tread nosings, or finish surface of ramp slope, shall be uniform, not less than 34 inches (864 mm) and not more than 38 inches (965 mm). Handrail height of alternating tread devices and ship ladders, measured above tread nosings, shall be uniform, not less than 30 inches (762 mm) and not more than 34 inches (864 mm).A.P.
24CALCULATIONSExample: 8 rooms of 50’, a room of 25’, 2 rooms of 10’,and a room of 60’.Find the width of the egress staircase? Step 1: times the # of rooms to there measurements. 8x50=400 1x25=25 2x10=20 1x60=60 All together =505 Step 2: Since our building is a institutional, please see table one and to determine the width of the stairs, have the total times o x 505 = –is the min width for stairs.Team
25CalculationsStep 3: knowing the min width for stairs can help you determine how many stairs you need. Remember you need 2 means of egress. Options: 2 stairs or 3 stairs 151.5/2=75.75’ 151.5/3=50.5’ 75.75’ as width for 50.5’ as width for each each stair case stair case Over all you can alter the width of the stairs, but as long as it over 44” which is required by code because building is commercial, the stairs will work.Team