Clause 6.6 Lifts
6.6.1 General
All lift installations and operations shall comply with SS 550 except as herein modified for the lift(s) in the station used for the safe evacuation of PWD.
6.6.2 Vent openings in lift hoistway
a. The protected lift shaft shall be vented in accordance with SS 550. The vents shall be so arranged as to induce exhaust ventilation of the shaft. Where vents could not be provided because of the location of the lift shaft, ventilation duct protected by drywall complying with Cl.3.8.8b. serving as ventilation of the shaft can be provided instead. If the duct is not to be fire-rated, fire dampers shall be provided to the duct at the wall of the lift shaft, provided such relaxation shall not apply to shaft containing fire lift.
b. Where the lift shaft is not a protected shaft, the lift hoistway shall be adequately ventilated at the top of the shaft by means of one or more permanent openings having a total unobstructed area of at least 0.1m2 for each lift in the shaft.
6.6.3 Dual electric feeder power supply
All lifts shall be provided with the dual electric feeder to allow the lifts to continue to operate during emergency without homing.
6.6.4 Hydraulic lift
Emergency lift control during power failure and/ or fire emergency for hydraulic lifts shall also comply with Cl.6.6.3 and the requirements of SS 550 respectively.
6.6.5
The power supply to the lift shall be connected to a sub-main circuit exclusive to the lift and be independent of any other main or sub-main circuits. The power cables serving the lift installation shall be routed through an area of negligible fire risk.
6.6.6 Fire lift
a. General
(1) The installation of the fire lift shall be in accordance with SS 550.
(2) All aboveground stations shall be provided with at least two fire lifts if the habitable height exceeds 24m.
(3) For underground stations where the depth between basement 1 finished floor level to the lowest storey finished floor level (cable chamber/ under-platform is not considered a storey) exceeds 9m shall be provided with at least one fire lift. All passenger lifts to double up as secondary fire lift for use by firefighters and be fitted with fire lift switches and emergency supplies.
(4) The fire lift shall be contained within a separate protected shaft or a common protected shaft containing other lifts subject to such other lifts being served at each storey by a fire lift lobby. Basement 1 can be considered as designated firefighters entry floor if the proposed fire lift cannot be extended directly to grade without transfers. Secondary fire lift need not be contained within a separate protected shaft and being served at each storey by a fire lift lobby.
R Rationale - Clause 6.6.6a.(4) To align with Fire Code on the need for fire lifts to be based on height rather than number of storeys as future stations are getting deeper. This facilitates firefighters bringing equipment down into the station and carrying out firefighting and rescue operations.The height can be measured from basement 1 instead of grade level to the lowest level of the station (excluding cable chamber or under-platform services ducts) for the following reasons:
a. Basement 1 is accessible via passenger lifts from multiple entrances compared with the previous situation where entrance into the basement(s) of a station is via a single firefighting lift shaft;
b. The entrances, subways and basement 1 public areas are all constructed in non-combustible materials and well-ventilated with fresh air supply being drawn in from each of the entrances; and
c. The basement 1 can be considered a safe area to reach the fire lift.
(5) The fire lift shaft shall be continuous throughout the station and serve every storey except a non-habitable roof. The fire lift operational features shall be provided and activated via a fire lift switch in accordance with SS 550 except all secondary fire lifts serving from grade level to all public areas.
(6) A lift mainly intended for the transport of goods shall not be designated as a fire lift. Cargo lift shall not open into a fire lift lobby.
R Rationale - Clause 6.6.6a.(6)It is common to find goods being stacked in lobby outside good lifts. This would affect the firefighters while carrying out firefighting operations during an emergency.
(7) The fire lift car shall have a platform area of at least 1.45m2. Where a fire lift serves the dual purpose of an evacuation lift for PWDs, it shall have a clear car platform area of minimum 1.2m by 1.4m.
b. Accessibility and coverage
(1) A fire lift shall be located such that the travel distance between the nearest edges of the lift landing door and exit staircase door is not more than 5m. In addition, the exit staircase shall be approached through a fire lift lobby at each storey, including first storey.
(2) Regardless of whether the station is installed with an automatic sprinkler system, the number of fire lifts required shall be such that any part of a storey of the station is within 60m coverage from the fire lift door, subject to the provision of at least two fire lifts in accordance with Cl.6.6.6a., except for underground stations.
c. Fire lift switch
A fire lift switch shall be provided at both the designated and alternate designated floors.
6.6.7 Passenger lifts designated for PWDs
Passenger lifts in stations are primarily provided for use by PWDs. These lifts that are located in the public area shall be used for the evacuation of PWDs during an emergency.
a. All passenger lifts in transit stations shall be used to evacuate PWDs in the event of fire emergency.
b. Passenger lift shall have a clear platform size of at least 1.2m (width) x 1.4m (depth).
c. Where passenger lifts in transit stations are located within the public area and within one fire compartment, the lift shafts are not required to be fire-rated. It is also not required to provide fire-rated lift lobby at lift landings.
d. From the platform level, PWDs shall use the passenger lift to reach the concourse level. Where concourse level is not the ground level, the PWDs shall be transferred to another lift that is connected to the ground level upon arrival at that concourse level. Directional signage shall be provided on the concourse level to direct PWDs to the lift(s) in accordance with the authority having jurisdiction on Accessibility in the Built Environment.
e. In the event of fire emergency, passenger lifts are not required to home to the designated floor. Passenger lifts are to be operated as in under normal conditions for use by PWD to evacuate the station. Car call control within the lift car shall operate as per normal.
f. Appropriate signage on the use of lift during emergency i.e. “In the Event of Emergency, Lift for Use by Persons with Disabilities Only” shall be displayed at the lift landing.
g. Lifts in transit stations shall be provided with electrical power supply from the RTS dual-feeder electrical power supply system for uninterrupted operation during fire emergency.
h. Except on the designated floor as defined in SS 550, emergency fire phone shall be provided at each lift landing for PWD to communicate with the Passenger Service Centre (PSC). In the absence of PSC, the emergency fire phone provided at each lift landing shall be connected to the OCC.
6.6.8 Homing of lifts
a. For stations requiring fire alarm system
(1) In a fire emergency, when any one of the fire detection devices or fire alarm systems is activated, all lifts except passenger lifts shall be brought to the grade or designated firefighters entry floor. Otherwise, the lifts shall home to an alternate designated floor (if the designated floor is a fire floor) and park with the lift landing doors remaining opened.
(2) Goods lifts with automatic doors shall be similarly homed to the designated floor.
(3) Goods lifts with manual doors shall be homed if the doors are closed.
b. Requirements for alternate designated floor
(1) An alternate designated floor (e.g. 2nd storey) shall be identified.
(2) All lifts except passenger lifts shall be brought to the alternate designated floor in the event of a fire at the designated floor.
(3) Localised detectors
(a) Localised detector(s) shall be provided to cover the lift landing space at the designated floor.
(b) The activation of any of the localised detector(s) or any other detectors or sprinklers covering the designated floor shall cause all the lifts to be re-directed to home to the alternate designated floor.
(c) The localised detector(s) shall cover the area within at least 3m surrounding the lift landing door opening.
(d) Where the lift landing is protected by a fire-rated enclosure, only the space within the enclosure is required to be covered by localised detector(s).
(4) The alternate floor shall have minimum fire hazard, and where people can escape to safety in an exit staircase or other exit from the lift landing door.
(5) In station that are not provided with sprinklers or automatic fire alarm system, suitable sensors shall be provided at the ceiling level to cover the lift landing space. The activation of any sensor shall cause the lifts to be re-directed to home to the alternate floor.
6.6.9 Provisions for lift rescue
a. General
The following requirements shall apply to station with blind lift hoist ways exceeding 11m. They shall be read in conjunction with SS 550.
b. Rescue hooks
(1) When the distance between consecutive lift landing doorsills is more than 11m but less than 18m, as shown in Diagram 6.6.9b.(1) – 1, rescue hooks complying with Cl.6.6.9b.(3) shall be provided at the underside of the upper lift landing door head. See Diagram 6.6.9b.(1) – 2.
(2) Alternatively, these hooks shall be installed in the ceiling space directly above the upper lift landing door, such that the heights of these hooks are not more than 3m above the finished floor level of that upper lift landing, and at an approximate distance of 1m away from the lift shaft wall. The ceiling space shall be easily accessible, and a sign shall be provided to indicate the locations of the rescue hooks. See Diagram 6.6.9b.(2) – 1 & 2.
(3) Rescue hook design
Each rescue hook shall have pull-out strength of at least 1000kg (10kN) and a thickness of at most 14mm in diameter. The clear space between the hook and the emergency door frame shall not be less than 100mm, and the spacing between the two hooks shall be between 500 to 700mm. See Diagram 6.6.9b.(3).
c. Landing emergency doors
(1) Where the distance between consecutive lift landing doorsills exceeds 18m, intermediate landing emergency doors shall be provided, such that the distance between sills is at most 18m. However, for adjacent cars fitted with car emergency doors complying with Cl.6.6.7d., intermediate landing emergency doors are not required.
(2) The landing emergency doors shall conform to all the following requirements. See Diagram 6.6.7c.(2):
(a) The dimension of landing emergency doors shall comply with the requirements of SS 550.
(b) They shall be easily accessible and free from fixed obstructions.
(c) They shall be either of the horizontally sliding or swinging single-leaf type.
(d) They shall be self-closing and self-locking and shall be marked in letters not less than 50mm high: “DANGER, LIFT WELL”.
(e) They shall be provided with a landing door lock which can be unlocked only from the landing side through the use of a key. The lock shall not be unlocked by any key which will open any other lock or device used for any other purpose in the building/ station. The key shall be kept where it is accessible only to authorised persons.
(f) Each door shall be provided with an electrical contact, the opening of which will render the lift inoperable.
(g) Two rescue hooks complying with Cl.6.6.7b.(3) shall be provided at the underside of each emergency door head. Alternatively, these hooks can also be installed in the ceiling space as stipulated under Cl.6.6.7b.(2).
d. Car emergency doors
(1) When car emergency doors are provided in adjacent cars to permit the lift-to-lift rescue and evacuation of passengers, there is no limit on the maximum allowable length of the blind lift hoist way. See Diagram 6.6.9d.(1).
(2) When car emergency doors are provided, all of the following requirements shall be complied with. See Diagram 6.6.9d.(2):
(a) The horizontal distance between cars shall comply with the requirements of SS 550.
(b) The dimension of car emergency doors shall comply with the requirements of SS 550.
(c) Car emergency doors shall be openable from outside the car without a key and from inside the car using a key.
(d) Car emergency doors shall open towards the inside of the car.
(e) Car emergency doors shall not be located in the path of a counterweight or in front of a fixed obstacle (except for beams separating the cars) preventing passage from one car to another.
(f) A portable/ movable bridge or a bridge integrated into the car complying with the requirements of SS 550 shall be provided.
(g) Each car emergency door shall be provided with an electric safety device, the opening of which will render the lift inoperable. A safety feature to prevent the lift from operating when the bridging plate or the handrail is deployed shall also be provided.