ESW- 11 :- Working on a Machine-Room-Less (MRL) Elevator: Hazards and Safety Controls

A machine-room-less (MRL) elevator has no separate machine room. The drive machine, usually a compact gearless motor, is installed inside the hoistway, often at the top of the shaft. The controller is usually in a cabinet at a landing, such as beside the top landing door frame, or in the shaft itself. Because the equipment is inside or next to the hoistway, technicians do more of their work in confined shaft spaces. The main hazards are therefore a mix of machine room, car top, and pit hazards. The controls below help technicians work safely.

How MRL Elevators Differ

The machine and sheaves are in the hoistway, so work on them often means standing on the car top, a platform, or a ladder.
The controller and main switch are often at a landing or in a cabinet near the shaft instead of in a machine room.
Many MRL lifts have an emergency and test operation panel, where rescue and testing functions are done from outside the shaft.
Headroom and pit space are often tight, so refuge spaces and mechanical blocking devices matter even more.
Many MRL lifts use steel belts or small-diameter ropes. Check the manufacturer’s inspection requirements for these.
Under IS 17900, MRL lifts are now covered together with traction and hydraulic lifts. The earlier standard for MRL lifts, IS 15785, has been replaced.
The machine may sit on the guide rails, on the shaft wall, at the top of the shaft, or in the pit. The location decides where you must stand, which hazards you face, and which protective devices you need.
Some designs have the machine and controller in the same cabinet or in a small service space. Others have a remote drive cabinet on a different floor.
Because the work area is the shaft itself, the lift cannot be treated as “off” just because the car is out of the way. Other people may still ride it or open its doors.
Compact machines and drives are often more densely packed than traditional equipment, which leaves less space for hands, tools, and escape.
Maintenance, tests, and rescue may need to be done from the landing and the emergency panel, so technicians must know the model’s specific procedures.

Hazards of Working on an MRL Elevator

Falls

Falling into the shaft from the landing, car top, or a work platform.
Falling objects: tools or parts dropped onto people below.
Ladders and platforms: unstable access to the machine at the top of the shaft.
Working at the top of the shaft: limited foothold, reaching overhead, and awkward positions.
Stepping between the landing and the car top: the gap and height difference can cause a fall or a trapped foot.
Slippery surfaces: oil, grease, or dust on the car top, platforms, and pit floor.

Moving and rotating equipment

Rotating machinery: the motor, sheave, and brake can catch hands, clothing, or tools.
Moving ropes or belts: ropes and belts running over the sheave can pull in hands or tools.
Crushing: being trapped between the car or counterweight and the shaft wall, the overhead, or the pit floor.
Unexpected car movement: from a brake fault, a control error, or manual brake release.
Counterweight and adjacent shafts: moving equipment close to the work area.
Overspeed governor and safety gear: spring-loaded or moving parts can trap or strike fingers and hands.
Moving doors: car and landing doors can close on hands or fingers.
Brake release: the car may drift in either direction, depending on how the load compares with the counterweight.

Electrical

Electric shock from the controller, drive, and wiring.
Stored energy: capacitors in the drive and rescue batteries can hold a charge after the power is off.
Arc flash: a short circuit in the controller or main panel can cause burns.
Live backup supplies: emergency lighting, rescue devices, and the alarm may stay live.
Damaged cables and fittings: worn insulation, loose terminals, and cables running close to moving parts.
Water and moisture: leaks, condensation, or wet pits near electrical equipment.
High-voltage drive circuits: modern drives use high DC bus voltages and can remain dangerous after the main switch is off.

Space and environment

Limited headroom and refuge space at the top of the shaft and in the pit.
Confined space: tight working areas can restrict movement and rescue.
Heat: the machine and drive can heat the shaft, and ventilation may be limited.
Poor lighting: shadows hide hazards.
Noise: operating machinery can be loud and hide warnings.
Public access: controller cabinets at landings may be near people who are not trained.
Fire: oil, grease, rubbish, and electrical faults in a confined shaft.
Poor air quality: dust, fumes from nearby work, and limited ventilation.
Fatigue and discomfort: long periods in cramped positions can reduce alertness and cause strain injuries.
Other trades: workers above or below you, especially in buildings that are still under construction.

Safety Controls

Before You Start Work

Plan the job and complete a risk assessment, and discuss it with your co-worker.
Read the manufacturer’s service manual for the specific MRL model. The location of the machine, controller, and emergency panel differs from model to model.
Tell your supervisor or building representative where you will be working.
Put “Out of Service” signs at the landings and barricade the entrances.
Check that no one is in the car before you take the lift out of service.
Check that the shaft lighting works, and carry a torch as a backup.
Wear the required PPE, including a hard hat, safety shoes with good grip, and eye protection where needed.
Wear a full-body harness wherever there is a fall hazard, and anchor it to an approved point.
Remove loose clothing and dangling jewelry, and tie back long hair.
Tie your tools to you or place them in a bag so they cannot fall.
Review previous service records and any open defect reports for the lift.
Confirm that you have the right tools, spare parts, and PPE before you go to the site.
Confirm that the blocking devices, props, and other protective equipment for this model are available and in good condition.
Do not start work if you are unwell, tired, or under the influence of anything that affects your alertness.
Check the weather, building occupancy, and other trades on site, since they can change the risk.

Access to the Controller and Emergency Panel

Keep the controller cabinet locked, and allow only authorized persons to open it.
Keep access to the main switch, controller, and emergency panel clear at all times.
Know the location of the main switch, the nearest stop switch, and the emergency panel before you start.
Make sure the main switch is labeled for the correct lift and can be locked out.
Do not store tools or materials in front of the controller cabinet or inside it.
Close and lock the cabinet when you leave, even for a short time.
Keep the area around the cabinet well lit and free of obstructions, with enough space to work and to escape.
Post warning signs on or near the cabinet, such as “Authorized Persons Only” and “Danger: Electrical Hazard.”
Label switches, fuses, and terminals clearly so you can identify the right circuit.
Keep wiring diagrams and the emergency procedure accessible near the controller.

Electrical Safety

Switch off the power to the lift before working on any part of it.
Never assume that a stop switch isolates the circuit you are working on. Stop switches are designed to stop the lift, not to isolate every circuit.
Apply lockout and tagout to the main switch when your procedure requires it, and keep the key with you.
Test your meter on a known source before and after you check for voltage.
Treat every circuit as live until you have proven that it is dead.
Wait for drive capacitors to discharge as the manufacturer instructs, and check for residual voltage before you touch them.
Check for backup supplies, such as rescue batteries, that may stay live.
Use insulated tools, and keep your hands and the work area dry.
Do not work on live circuits unless it is necessary, your procedure allows it, and you are qualified.
Use arc-rated PPE where there is an arc-flash risk.
Use only calibrated meters rated for the voltage you are working on.
Remember that control systems may be electrically interconnected, so a circuit may be live even when the lift you are working on is off.
Isolate rescue batteries and emergency power supplies when the manufacturer’s procedure requires it, and reconnect them before you return the lift to service.
Keep cables and test leads away from moving parts and ropes.
Account for every jumper you use, tag it, and remove all jumpers before returning the lift to service.
Keep cabinet and panel doors closed when you are not working on them.

Working at the Machine in the Shaft

Switch off the lift and isolate the power before working on the machine, brake, or sheave.
Put the lift in inspection mode when you need to move the car to reach the machine.
Use a platform, ladder, or the car top designed for the task. Do not use makeshift steps or climb on equipment.
Mechanically secure the car, for example with the manufacturer’s blocking or locking device, before working in the shaft where the car could move.
Keep your hands, tools, and clothing away from the sheave, ropes, belts, and brake.
Do not lean on the machine or on ropes for balance.
Do not clean, oil, or grease moving parts while the machine is running.
Hold wiping cloths in your palm, and never wrap them around your hand.
Do not wear gloves near rotating machinery.
Be careful of hot surfaces on the machine and drive.
Wear hearing protection if the machine or tools are loud.
Do not rely on the machine brake alone to hold the car while you work. Use the mechanical device the manufacturer provides.
Check that the platform or working position is stable, level, and rated for your weight and equipment.
Use fall protection wherever there is an open edge, and keep your lanyard clear of moving parts.
Support heavy components, such as the machine, brake, and sheave, with proper lifting equipment, and never stand under a suspended load.
Handle belts and ropes only as the manufacturer instructs, and keep your fingers out of pinch points.
Do not remove guards or covers except for the task, and replace them before you leave.
Check bolts, brackets, and fixings on the machine and guide rails with the right tools, and use a torque wrench where the manufacturer specifies it.
Keep oil, grease, and cleaning materials away from the brake and braking surfaces.

Working on the Car Top

Follow the car top controls in your car top procedure. In particular, put the lift in inspection mode, test the stop switch and inspection switch, and set the stop switch to STOP before you work on equipment.
Move the car only in inspection mode, with the doors closed, and tell your co-worker the direction before you move.
Know the refuge space on the car top, and the overhead clearance, before you move the car upward.
Never ride on the car top at normal speed.
Do not lean over the edge or let anything project into an adjacent shaft.
Keep tools and materials secured so that they cannot fall into the shaft.
Check that the car top inspection station, stop switch, and direction buttons work correctly before you rely on them.
Open the landing door only a little (for example, 15 cm) at first, and confirm that the car is present before you open it fully.
Mechanically block or hold the landing door open, and never leave it open and unattended.
Stand where you can reach the stop switch at any instant, and keep all parts of your body inside the car limits while it moves.
Keep clear of the ropes, belts, and any equipment mounted on or above the car.
Watch for equipment mounted on the car top or at the top of the shaft that moves with the car, such as pulleys, diverter sheaves, and cables.
Move slowly near the top of the shaft, and stop to check the clearance before you go further.

Working in the Pit

Open the pit stop switch before you enter, and verify that the car will not move.
Use the access ladder, and never jump down into the pit.
Turn on the pit light before you start work, and check for water, oil, and debris.
Use the mechanical props or blocking devices provided when you work under the car.
Stay clear of the counterweight, buffers, and moving ropes.
Do not stay in the pit while the lift is running on automatic.
Do not work directly above or below another person.
Know where the pit refuge space is, and use it when the car moves.
Do not enter a flooded pit. Isolate the power and report the water to building management.
Do not stand on the buffers.
Keep the pit clean, dry, and free of stored materials.
Do not leave tools or equipment in the pit when you leave.
Test the pit stop switch before you start work, and deactivate it only after you have left the pit.
Where the machine or drive is in the pit, apply the manufacturer’s isolation and blocking procedure before working on it.

Manual Rescue and Brake Release

Only trained and authorized persons should perform rescue operations.
Use the emergency and test operation panel, and follow the manufacturer’s procedure for the specific model.
Check that all landing doors are closed and that no one is in the shaft or on the car top before you move the car.
Be aware that the car may move in either direction when the brake is released, depending on the load in the car compared to the counterweight.
Release the brake gradually, and stay clear of rotating parts.
Never enter the shaft or open the car door from the landing to rescue someone unless you are trained and the lift is secured.
Return the equipment to its normal state afterward, and check that the brake works before putting the lift back in service.
Switch off the main switch before you use a manual or powered rescue device, unless the manufacturer says otherwise.
Communicate with the passengers throughout the rescue. Tell them what you are doing, and ask them to stay still and away from the doors.
Use the floor indicator or position display on the panel to find where the car is, and move it only as far as the nearest landing.
Once the car is at a landing, open the doors with the correct key, help passengers out one at a time, and check that nobody needs medical help.
Keep a record of the rescue, including the cause, actions taken, and any injuries.
Do not return the lift to service until the cause of the stoppage has been found and corrected.

Testing and Commissioning

Run safety tests, such as governor and safety gear tests, overspeed tests, brake tests, and buffer tests, only when your procedure and training allow.
Keep people out of the shaft and pit when you run tests that move the car at speed or apply loads.
Check that all the safety devices are working after tests: door locks, stop switches, final limit switches, and the safety circuit.
Check that unintended car movement protection, ascending car overspeed protection, and the emergency lighting and alarm work, where fitted.
Record test results, and keep the records with the lift documents.
Only a competent person, using calibrated equipment, should carry out and sign off the tests.

Maintenance of Belts, Ropes, and Gearless Machines

Inspect ropes and belts at the intervals the manufacturer sets, and look for wear, broken strands, corrosion, cracks, and uneven tension.
Replace ropes or belts when they reach the discard criteria. Never reuse damaged ones.
Do not lubricate belts or ropes unless the manufacturer says that it is required.
Check sheaves and diverter pulleys for wear and alignment.
Check the brake lining wear, brake gap, and holding performance on schedule.
Check bearings, the encoder, and mounting bolts for looseness or abnormal noise.
Keep the machine clean and free of oil leaks and dust.
Use only manufacturer-approved parts and lubricants.

Falls and Falling Objects

Barricade open landing doors, and never leave a landing door open and unattended.
Keep tools and materials away from open shaft openings and platform edges.
Do not work above or below another person unless protection is in place.
Keep the shaft free of rubbish and loose materials.
Use debris netting or overhead protection where people are working at different levels in the same shaft.
Secure tools with lanyards, and use tool bags, not pockets.
Keep the area at the landing free of people when you work above, and put up warning signs.
Do not drop tools or parts to a colleague. Hand them over or lower them with a rope.

Fire, Housekeeping, and Environment

Keep the shaft, car top, and pit clean and free of oil, grease, and rubbish.
Put oily rags in a covered metal container, and take them out of the building.
Keep a suitable fire extinguisher at the work location, and know how to use it.
Do not smoke, and keep flames and sparks away from the shaft.
If you do hot work, such as welding or grinding, follow your site’s hot-work permit and fire-watch procedures.
Keep ventilation openings clear, and report overheating or failed ventilation to building management.
Take breaks and drink water in hot conditions.

Communication and Lone Working

Keep communication open with your co-worker, and agree on clear signals.
Avoid lone work in the shaft where your procedure requires a second person.
If you must work alone, arrange check-in times and carry a working phone or radio.
Tell your colleague before you move the car, change position, or stop work.
Tell building management and nearby occupants before work begins, and again when it finishes.
Keep other trades and the public away from open landing doors and work areas.
Never accept work instructions from anyone who is not authorized.

Emergencies

Know the location of the nearest stop switch, first-aid kit, fire extinguisher, and exit.
If someone is injured or trapped in the shaft, call for help immediately, and do not enter the shaft unless the hazards are controlled and you are trained.
If someone is suspended in a harness, call for help immediately. Suspension can become dangerous within minutes, so a rescue plan is essential.
If someone suffers an electric shock, switch off the power first if it is safe to do so, and do not touch the person until the supply is off.
If you smell smoke or see fire, stop work, raise the alarm, and evacuate.
Report every injury, near miss, and unsafe condition to your supervisor.
Know how to switch off the power in an emergency, including the main switch location.
Keep a list of emergency contacts, including the elevator contractor, building management, and emergency services.
Never attempt a rescue of passengers unless you are trained and authorized.
After an incident, do not return the lift to service until it has been inspected and cleared.

Before Returning the Lift to Service

Remove all tools, rags, and materials from the car top, pit, and landing.
Remove blocks, props, and barricades that you placed.
Remove all jumpers, locks, and tags, and test the safety circuits.
Replace all guards and covers, and close and lock the controller cabinet.
Return the stop switches and inspection controls to normal, and run the lift to check stopping, leveling, and door operation.
Remove “Out of Service” signs, and tell building management what was done and any concerns.
Check that no person, tool, or material is left in the pit, on the car top, or in the shaft.
Check that all landing doors are closed and locked.
Test the alarm, intercom, and emergency lighting.
Record the work done, parts used, and defects found, and report any open issues.

Quick Checklist for MRL Technicians

Do I have the manufacturer’s manual for this model?
Is the lift isolated, locked out, and tested dead?
Are the blocking devices or props in place?
Is my harness anchored, and are my tools secured?
Do I know the refuge spaces and the position of the stop switches?
Does my co-worker know where I am and what I am doing?
Have I tested the stop and inspection switches before I rely on them?
Is everything removed, replaced, tested, and recorded before I leave?

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