Escalators are equipped with a variety of safety protection systems designed to ensure safe and reliable operation for passengers. These systems work together to monitor the equipment, prevent accidents, and respond quickly to abnormal conditions. Common safety features include emergency stop buttons located at both ends of the escalator, which allow passengers or staff to immediately halt operation in case of danger.
In addition, escalators are fitted with skirt guards and step-edge safety devices to reduce the risk of entrapment between moving steps and side panels. There are also sensors that detect issues such as step chain failure, overspeed, or motor overheating, automatically stopping the escalator to prevent further damage or injury. Handrail speed monitoring systems ensure that the handrail moves in sync with the steps, providing stability for users.
Escalator Safety Devices
Escalator Chain Breakage Protection Device
The escalator stops operating when the step chain is overstretched or breaks. The safety switch manually resets after the fault is cleared.
Handrail Entry Safety Device
The escalator stops operating when an object gets caught in the handrail entry. The safety switch automatically resets when the fault is cleared.
Emergency Stop Button
There is a red emergency stop button on the control panel at the escalator entrance. In case of an emergency, the escalator can be stopped immediately.
Skirt Protection Device
The escalator stops operating when an object becomes trapped between the footplate and the skirt panel. The safety switch automatically resets upon troubleshooting.
Escalator Safety Device
The escalator will stop operating if it sinks, deforms, or breaks. The safety switch will manually reset after the fault is cleared.
Comb Tooth Protection Device
If a foreign object carried by a step enters the comb teeth and may damage them, the escalator will stop operating. The safety switch will automatically reset when the fault is cleared.
Non-operational Reverse Protection Device
When the escalator suddenly reverses direction without human intervention (due to power grid reversal, overload, drive chain breakage, etc.), the escalator will stop operating.
Speed detection Device
The escalator will stop operating when its speed exceeds or falls below the rated speed.
Drive Chain Breakage Protection Device
The escalator stops operating when the drive chain is overstretched or breaks. The safety switch manually resets after the fault is cleared.
Motor Brake Detection Switch
Installed on the brake support plate to prevent the motor from starting before the brake is fully released.
Auxiliary Brake (abk)
ABK Classification
- The auxiliary brake and the drive wheel of the steps, pedals, or belt shall be connected by a shaft, gears, multi-row chains, or multiple single-row chains. Connections using friction transmission elements (e.g., clutches) are not permitted.
- The auxiliary brake shall be mechanical (utilizing the principle of friction).
Handrail Entry
- The distance h3 between the lowest point of the handrail at the handrail turning end entry and the floor should not be less than 0.1m or greater than 0.25m (see Figures 2 and 3).
- The horizontal distance 14 between the top of the handrail turning end and the handrail entry should be at least 0.30m. If 14 is greater than (12-13+50mm), the angle between the handrail and the horizontal direction when the handrail enters the handrail assembly should be at least 20°.
- Finger and hand protection devices should be provided at the handrail entry at the handrail turning end, and a safety device conforming to the requirements of i) in Table 6 should be provided.
Entrances and Exit
Escalators and moving walkways should have a safe foothold in the entrance and exit areas (e.g., comb support plates and floor slabs), with a depth of at least 0.85m measured from the root of the comb plate teeth (see L1 and sectional view X in Figure 2).
Comb Plate
- Comb plates should be installed at both ends of the entrance/exit for easy user access. Comb plates should be easily replaceable. The ends of the comb plates should be rounded, and their shape should minimize the risk of pinching between the comb plate and the steps, treads, or conveyor belt. The radius of the rounded corners at the comb plate ends should not exceed 2mm. The comb teeth of the comb plate should have a shape and angle that prevents users from tripping when exiting the escalator or moving walkway, as shown in the sectional view X of Figure 2, and the design angle should not exceed 35 degrees.
- The comb teeth of the comb plate should engage with the grooves of the steps, treads, or conveyor belt. The width of the comb teeth, measured at the tread position, should not be less than 2.5mm.
- The comb plate or its supporting structure should be adjustable to ensure proper engagement.
- The comb plate should be designed so that, even if a foreign object gets stuck, the comb teeth can still maintain normal engagement with the steps or treads under deformation or breakage.
- The meshing depth h8 between the comb teeth of the comb plate and the tread tooth groove should not be less than 4 mm. The clearance h6 should not be greater than 4 mm.
Machine Room, Drive Station, And Steering Station
If moving or rotating parts are easily accessible and pose a hazard to personnel, effective protective and guarding devices should be provided, especially for the following parts:
a) Keys and bolts on shafts;
b) Chains and drive belts;
c) Transmission mechanisms, gears, and sprockets;
d) Protruding parts of the motor main shaft;
e) Exposed speed limiters;
f) Steps and pedal steering parts in the drive station and/or steering station where maintenance must be performed internally;
g) Handwheels and brake discs (drums).
Dimensions And Equipment
- The machine room, especially the drive and steering stations within the truss structure, should have a sufficiently large standing space without any permanent fixed equipment. The standing area should be at least 0.3 m², with the shorter side not less than 0.5 m in length.
- If the control cabinet must be moved or lifted for maintenance purposes, suitable lifting accessories, such as eye bolts and handles, should be provided.
Stop Switches For Maintenance And Repair
Stop switches should be provided in both the drive and steering stations.
The operation of the stop switch should cut off the power supply to the drive unit, engage the working brake, and effectively stop the escalator or moving walkway.
After the stop switch is activated, it should prevent the escalator or moving walkway from restarting.
The stop switch should have clear and permanent on/off position markings.
The emergency stop device should be red and marked with the word "Stop" on or near it.
