Transcript egress presentation (group #2)

Means of Egress
Talia Ordonez
Alex Prodanov
Margarita Binkin
Team
What is the importance of egress?
To save lives.
T.O
Tragedies that created and
developed building codes.
One of the many tragic fires that shaped the
way buildings were design:
The Triangle Shirtwaist Fire
And
Iroquois Theater Fire
T.O
THE 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 workers
-Dozens 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 deaths
T.O
Stairways
NYC Building Code require
2 means of egress.
Egress extend from floor to ceiling to lead
everyone to the closest exit discharge.
T.O
Hallway
Signs
Egress
Corridor
Ramps
Lighting
Railing
Doors
T.O
Dimensions
T.O
Sprinkler Systems
T.O
Illumination
Lights are required to inform
and show people where the
nearest exists are.
T. O
ELEVATORS AND ESCALATORS ARE NOT
COMPONANTS REQUIRED MEANS OF
EGRESS IN ANY BUILDING
T.O
Iroquois 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 CHANGESThis 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.
Exit 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.
Horizontal exits- can serve as additional exits where there
is at least two or more exits
•
•
M.B.
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.
Exit discharge - serves as exit that leads directly to the
exterior of a building
•
•
•
M.B.
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.
Main exits
• Should 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 building
M.B.
Marking and symbols- should be provided in all
types of buildings except residential in case of
private houses
• Should 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.
Assembly 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.
Widths 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 0.005 inch (0.127 mm) of additional stair width for each occupant shall be provided for each 0.10
inch (2.5 mm) of riser height above 7 inches (178 mm).
•
3. Where egress requires stair descent, at least 0.075 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.
Travel Distance
• Exits and aisles shall be so located that the travel distance to an exit door shall not be greater
than 200 feet (60 960 mm) measured along the line of travel in nonsprinklered buildings. Travel
distance shall not be more than 250 feet (76 200 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 (60 960 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 (60 960 mm).
Exit access travel distance
A.P.
Common path of egress travel
A.P.
OCCUPANCY LOAD
A.P.
Doors
Size 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.
HANDRAILS
Handrail 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.
CALCULATIONS
Example: 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.3.
0.3 x 505 = 151.3 –is the min width for stairs.
Team
Calculations
Step 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
151.5/2=75.75’
75.75’ as width for
each stair case
or
3 stairs
151.5/3=50.5’
50.5’ as width for each
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