Standard for Fire Safety in Rapid Transit Systems - Singapore Civil ...

B.1.7 Where exit paths divide, i.e., where a choice of exit paths is
presented, it is presumed that the passengers will divide into
groups roughly in proportion to the exit capacity provided by
the various paths at the decision point. It also is presumed
that passengers, once having made a decision (selecting an
exit path), will stay on that path until another decision point
is reached or egress is achieved.
B.1.8 The waiting time at each of the various circulation elements
is calculated, for the platform exits, by subtracting the
walking travel time on the platform from the platform exits
flow time, and for each of the remaining circulation elements,
by subtracting the maximum of all previous element flow
times.
B.2 CENTRE PLATFORM STATION
B.2.1 The sample centre platform station shown in Figure B-2.1 is
an underground station with the concourse above the
platform level but below grade. The platform public area is
60m long to accommodate the train length. The vertical
distance from the platform to the concourse is 5m. The
vertical distance from concourse to grade is 8m.
The station has two entrances normally used by passengers.
Each of these entrances has two escalators of 1m clear width
and one stair of 2m clear width. The entrances are covered at
grade level to a point 9m beyond the top of the stair landing.
The station concourse level has one paid area separated from
the unpaid area. At two ends of the paid area, there are 8
electronic fare gates and a 1-m wide emergency gate. The
open well at the centre of the concourse level communicate
with the platform level. Each end has one stair of 2m clear
width and two escalators of 1m clear width. Station ancillary
areas are located at the two ends of the platform and
concourse level.
The station occupant load is 1200 persons.
In Test #1 of Figure B-2.2, the time to clear the platform is
found to be 2.86 minutes. This meets the requirement of
Cl.2.2.3.3. The sample calculation shows the effect of
discounting one of the escalators from platform to concourse
for the escape route to the right of the station.
In Test #2 of Figure B-2.2, the time to reach a point outside
Waiting time
at circulation
elements
Standard for Fire Safety in Rapid Transit Systems B-2