Many Schools have lifts these days and it is important that the lifts are regularly serviced and inspected, to prevent mechanical breakdown and to prolong the life of your lift. In my school, we have 4 passenger lifts and a larger Service Lift. There lifts are in various parts of the building and allow disabled people to access other floors in the building.
But what if the lift breaks down suddenly? All lifts these days, have alarms to call for help. Pressing the red alarm button in our lifts, connects the user to Switchboard during the day and the Sick Bay Nurses Station out of hours. Staff can then speak to the passengers and find out what the problem is. Normally, a lift breakdown is caused by a unplanned engagement of the emergency brake. This emergency break system, also prevents the lift from free-falling down the shaft and is controlled by a device called the Governor. The Governor uses. centrifugal force and moves a flyweights outward, pushing against a set of springs. When spinning in this position, the hooked ends of the flyweights catch hold of ratchets mounted to a stationary cylinder surrounding the sheave. This works to stop the governor.
The governor cables are connected to the lift car via a movable actuator arm attached to a lever linkage. When the governor cables can move freely, the arm stays in the same position relative to the elevator car (it is held in place by tension springs). But when the governor sheave locks itself, the governor cables jerk the actuator arm up. This moves the lever linkage, which operates the brakes.
In addition, lifts have have electromagnetic brakes that engage when the car comes to a stop. The electromagnets actually keep the brakes in the open position, instead of closing them. With this design, the brakes will automatically clamp shut if the elevator loses power. Also, in the unlikely situation that a passenger forced the car doors open, the electromagnetic breaks would clamp shut, against the running rails either side of the lift and bring it to a halt. Elevators also have automatic braking systems near the top and the bottom of the elevator shaft. If the elevator car moves too far in either direction, the brake brings it to a stop.
If all else fails, and the elevator does fall down the shaft, there is one final safety measure that will probably save the passengers. The bottom of the shaft has a heavy-duty shock absorber system — typically a piston mounted in an oil-filled cylinder. The shock absorber works like a giant cushion to soften the elevator car’s landing.
Anyway, that’s enough of the safety systems and how they work. Lets look at an emergency situation, where the lift is trapped between floors. In this scenario, the lift has developed a fault and is stuck between the 12st and ground floor of J Block.. The passenger presses the lift alarm for 5 seconds, which telephones Switchboard or Sick Bay. Sick bay or Switchboard will either radio me, if I am on site, or phone me if off site. If there is a medical emergency or if the passenger is extremely distressed, Switchboard \ Sick Bay will call the Fire Brigade to rescue the passenger and inform me of this.
The 1st job I will do, is to get the shaft key and open the doors on the ground floor and look up, to see whee the lift is stuck. I will then try to speak to the person stuck in the lift and tell them that I am here and that we will lower the lift shortly. I then will slide the shaft doors shut and lock with the shaft key. Now, I need to walk up 5 flights of stairs, to walk 5 flights of stairs to the locked roof access door, (Or take the Service Lift to the 4th floor, and walk the remaining 1 flight.) Once on the roof, I can access the locked Lift Plant Room. You’re first priority is safety and due to this, you need to switch off the lift machinery, via the main Isolator Switch. It is important that you also “Lock out, Tag out” the switch, to ensure that the power is not switched back on accidently. I am going to do another guide on this, in due course.
If you have the correct training in lift lowering, please continue reading this section. If not, please skip to the next section.
First, we need to pull the lever on the wheel that the main lift cables are connected to. This will release the brakes on the lift car. Don’t worry, the Governor will stop the lift from falling! On the same wheel, pull out the handle, which is connected to the motor. You will need to slowly wind this handle anti-clockwise. It will be heavy, due to the weight of the lift, so wind slowly and the lift will move safely and easily. Keep winding until you reach the bottom of the shaft. Also remember to re-engage the brakes!
Now go back downstairs and open the doors to the lift shaft. The lift should now be in the right position and you should be able to prise the doors to the lift car open. If the lift is not in line with the floor, you should help the passenger to “alight” the lift. The person who has been stuck in the lift, may be shaken up a little. So, a friendly hug of reassurance might be needed.
Now you need to lock the shaft doors shut and place a “out of order” sign on the door.
Once the lift engineer has been and fixed the problem, remove the Lockout Tag Out device and switch the power back on to the lift. Don’t forget to write an incident report and file it correctly, depending on the procedures, set out by your School or Local Authority.
Testing Your Lift
Every day, I inspect our lifts, checking the doors open and close properly, that the alarm sounds outside the lifts, the selective floor control operates. (This needs a key to do this) the lights work and the fan is running. The kift will be taken out if use, anything is at fault (use the selective Floor Controls to do this) and an engineer called.
Remember: Safety First!
- Lifts are dangerous, only attempt a lift rescue if you have had proper training of lowering a lift.
- Always switch off the power to the lift and use Lockout Tagout, to prevent the power accidently being switched back on.
- The lights, fan and alarm all have a battery backup on the roof of the lift car, so the lift won’t plunge into darkness!
- Take care not to fall into the lift shaft, when looking up from the open doors!
- Do not tell the passenger to force the car doors open. This could lead to injury or death and could also damage the lift car!
- If you are unsure how to proceed, call a qualified Lift Engineer!
- If the passenger is extremely distressed, dial 999 and ask for the Fire Brigade