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MEANS OF EGRESS. MEANS OF EGRESS. A means of egress is a continuous and unobstructed way of exit travel from any point in a building or structure to a public way and consists of three separate and distinct parts: - Exit Access - Exit - Exit Discharge. EXIT ACCESS.
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MEANS OF EGRESS • A means of egress is a continuous and unobstructed way of exit travel from any point in a building or structure to a public way and consists of three separate and distinct parts: - Exit Access - Exit - Exit Discharge
EXIT ACCESS • Portion of a means of egress which leads to an entrance to an exit. It includes the room or space in a building in which a person is located and the aisles, stairs, ramps, passageways, corridors and the doors that must be traversed on the way to an exit.
EXIT • Is that portion of a means of egress which is separated from all other spaces of the building or structure by construction or equipment as required to provide a protected way of travel to the exit discharge.
EXIT DISCHARGE • Is that portion of a means of egress between the termination of an exit and a public way
CAPACITY OF MEANS OF EGRESS • The occupant load in any building or portion thereof shall not be assumed to be less than the number determined by dividing the floor area assigned to the use of the occupant load factor. 1 Unit of Exit Width (UEW) = 55cm Capacity of Exit: Level egress component including class A ramps = 100 person/UEW (0.55cm/person) Inclined egress component including class B ramps = 60 person/UEW (0.92cm/person) Stairs = 45 person/UEW (1.22cm/person)
EXAMPLE Gross(Office)Floor Area = 1,860 sq. m. Occupant Load Factor = 9.3 gross sq.m. (OLF) per person Number of Occupant = GFA/OLF = 200 person
EXAMPLE • Gross Floor Area = 10,000 sq.m. • OLF (office) = 9.3 sq.m./person • No. of Occupant = 10,000/9.3 = 1,075.27 persons at level egress component: Total Width of Exit = 1,075 persons x 0.55cm/person TWE = 591.25 cm No. of exits = TWE/Width of Exit (ranges 71cm–122cm for doors) = 591.25cm/122cm = 4.85 say 5 exits of 122cm clear width
MEASUREMENT OF TRAVEL DISTANCE TO EXIT • The maximum travel distance to any occupied space to at least one exit, measure in accordance with the following requirements, shall not exceed the limits specified by the Codes.(Par 5-6.1,NFPA)
MEASUREMENT OF TRAVEL DISTANCE • The travel distance to an exit shall be measured on the floor or other walking surface along the centerline of the natural path of travel starting from the most remote point subject to occupancy, curving around any corners or obstructions with one foot clearance therefrom, and ending at the center of the doorway or other point at which the exit begins. Where measurement includes stairs, the measurement shall be taken in the plane of the thread nosing.
EGRESS COMPONENTS • Exit door swings in direction of egress • Exit doors are not locked when building is occupied • Exit doors are kept closed (doors close and latch) • Access to and from the exit is not obstructed
NFPA 80 • Chapter 15 – Care and Maintenance - Fire doors, shutters, and windows are of no value unless they are properly maintained and closed or are able to close at the time of fire. A periodic inspection and maintenance program should be implemented and should be the responsibility of the property management.
NFPA 80 • Chapter 15 – Care and Maintenance - Door openings and the surrounding areas shall be kept clear of anything that could obstruct or interfere with the free operation of the door.
NFPA 80 • Chapter 15 – Care and Maintenance - Blocking or wedging of doors in the open position shall be prohibited. - Self-closing devices shall be kept in proper working condition at all times.