SHARDA uNIVERSITY

Submitted By:-Ishan GargRajat AgrawalPikakshi Bharadwaj

SERVICES

Design of fire escapes

Fire escape:

• a special kind of emergency exit.

• provides a method of escape

• often found on multiple-

story residential buildings

• they have fallen out of common use

General Exit Requirements

An exit may be a doorway; corridor; passageway(s) to an

internal staircase, or external staircase, or to a

VERANDAH or terrace(s), which have access to the

street, or to the roof of a building or a refuge area. A exit

may also include a horizontal exit leading to an adjoining

building at the same level.

Lifts and escalators shall not be considered as exits.

Every exit, exit access or exit discharge shall be

continuously maintained free of all obstructions or

impediments to full use in the case of fire or other

emergency.

Every building meant for human occupancy shall be provided with exits

sufficient to permit safe escape of occupants, in case of fire or other

emergency.

In every building or structure, exits shall comply with the minimum

requirements of this part, excep those not accessible for general public use.

No building shall be so altered as to reduce the number, width or protection of

exits to less than that required.

Exits shall be clearly visible and the route to reach the exits shall be clearly

marked and signs posted to guide the occupants of the floor concerned. Signs

shall be illuminated and wired to an independent electrical circuit on an

alternative source of supply. The sizes and colours of the exit signs shall be in

accordance with good practice . The colour of the exit signs shall be green.

The floors of areas covered for the means of exit shall be illuminated to

values not less than 1 ft candle (10 lux) at floor level. In auditoriums, theatres,

concert halls and such other places of assembly, the illumination of floor

exit/access may be reduced during period of performances to values not less

than 1/5 ft candle (2 lux).

Fire doors with 2 h fire resistance shall be provided at

appropriate places along the escape route and

particularly at the entrance to lift lobby and stair well

where a ‘funnel or flue effect’ may be created, inducing

an upward spread of fire to prevent spread of fire and

smoke.

All exits shall provide continuous means of egress to the

exterior of a building or to an exterior open space leading

to a street.

Exits shall be so arranged that they may be reached

without passing through another occupied unit.

Economic Aspects Of Fire:

Losses & Expenditure…

• lives

• Property

• Use

• by Injury

• suppression

• prevention

• protection

• insurance

• research &

development

ESCAPE ROUTES:

There must be at least one escape route from

a. the main entrance door of every flat or maisonette

b. the door of every communal room

c. from every plant room.

An escape route must lead to a place of safety

a. directly

b. by way of a protected zone

c. by way of an access deck or access balcony

In case of under ground fire

Egress windows…

Windows Below Ground Level:

a)Sill height of window above floor: Not to exceed 1100 mm

b)Minimum opening area: 5.7 sq. ft.

c)Minimum opening height: 600 mm

d)Minimum opening width: 500 mm

HOW To ESCAPE THE FIRE…

Escaping with elevators.

Escaping through staircases.

Rescuing people by firemen and rescue

services.

Rescuing with a telescopic ladder.

Rescuing people through the windows.

Emergency escaping with the 'rescue

hose'

four distinct Stages:

Stage 1 – escape from the room or area of fire origin.

Stage 2 – escape from the compartment of origin via the circulation route to a protected stairway or an adjoining compartment offering refuge.

Stage 3 – escape from the floor of origin to the ground level.

Stage 4 – escape at ground level away from Building.

Means of escape from fire…

Time of evacuation

Travel distances

Capacity of Exits

Calculation of Exit Widths

Calculation of Minimum Number of Exits

Time of evacuation:

Class ‘A’ construction – 3 minutes

Class ‘B’ construction – 2.5 minutes

Class ‘C’ construction – 2 minutes

CAPACITY OF EXITS

The unit of exit width, used to measure the capacity of any

exit, shall be 500 mm. A clear width of 250 mm shall be

counted as an additional half unit. Clear widths less than 250 mm shall not be counted for exit width.

NOTE — The total occupants from a particular floor must evacuate within

2½ minutes for Type 1 construction, 1½ minutes for Type 2 construction

and 1 minute for Type 3 construction. Size of the exit door/exitway shall be

calculated accordingly keeping in view the travel distance as per Table

22.

Occupants per unit exit width shall be in accordance with

Table 21.

Travel Distance:

Places of Relative Safety A storey exit into a protected stairway or to the

lobby of a lobby approach stairway;

A door in a compartment wall or separating wall

leading to an alternative exit;

A door which leads directly to a protected stair or a

final exit via a protected corridor.

Calculation of Exit Widths

U = N / (40 x T)

Where: -

U = number of units required;

N = number of occupants;

40 = standard rate of flow – constant;

T = Flow time (i.e. 3 mins for Class ‘A’, 2.5 mins for

Class ‘B’ and 2 mins for Class ‘C’)

Calculation of Minimum Number of Exits E = U / 4 + 1

E = number of exits

U = number of units of exit width (from exit width

formula);

4 = size of largest exit permitted.

1 added to ensure there would always be at least

one unit.

Doorways Every exit doorway shall open into an enclosed stairway

or a horizontal exit of a corridor or passageway providing continuous and protected means of egress.

No exit doorway shall be less than 1 000 mm in width

except assembly buildings where door width shall be not

less than 2 000 mm. Doorways shall be not less than 2 000

mm in height.

Exit doorways shall open outwards, that is, away from

the room, but shall not obstruct the travel along any exit.

No door, when opened, shall reduce the required width of stairway or landing to less than 900 mm; overhead or

sliding doors shall not be installed.

Exit door shall not open immediately upon a flight of stairs;

a landing equal to at least the width of the door shall be

provided in the stairway at each doorway; the level of

landing shall be the same as that of the floor which it

serves.

Exit doorways shall be openable from the side which they

serve without the use of a key.

Mirrors shall not be placed in exit ways or exit doors to

avoid confusion regarding the direction of exit

Methods & Designs practiced

for escaping fire…

PRESSURISED STAIRCASE

functioninga) A Supply Air System designed

to blow into the protected

spaces a sufficient quantity of

air to maintain the required

pressure level or air velocity.

This will always be fan powered.

b) An Exhaust Air System to

enable the pressurising air to

escape from the unpressurised

areas of the building via the

fire floor.

This can be either a natural or fan

powered method.

Escape chute

system: Vertical escaping chute

Inclined chute

Single entry chute

Multiple entry chute

Residential chute

Vertical

chute:

Inclined chute

• prefer to slide to safety, rather than escape vertically.

Single

entry

chute &

multiple

entry

chute

Residential chute

• Weighing 13kgs / 28lbs the

frame can be carried from one

room to another, or from one

balcony to another on the

same level.

Hanging rope fire

escape:

Fire escaping stairs

A fire escaping stair is a special kind of emergency exit,

usually mounted to the outside of a building or occasionally inside but separate from the main areas of the building.

Escaping stairs..

• Drop ladder

Counterbalanced Stairs

• Gooseneck ladder

THANK YOU…