The machine room (also called the motor room) houses the elevator’s drive machine, controller, brake, and main power supply. Technicians work close to rotating machinery and live electrical equipment, so a few simple controls make a large difference to safety.
Hazards in the Machine Room
Moving and rotating equipment
- Rotating machinery: the motor, sheave, and other moving parts can catch clothing, hands, or tools.
- Unexpected start-up: machinery can start without warning.
- Moving ropes: ropes running over the sheave can pull in hands, tools, or clothing.
- Overspeed governor and brake: moving or spring-loaded parts can strike or trap fingers.
- Manual rescue operation: releasing the brake or turning the machine by hand can move the car unexpectedly.
Electrical
- Electric shock: live equipment and interconnected control circuits can cause serious injury.
- Arc flash and burns: a short circuit in the controller or main panel can cause a severe arc flash and burns.
- Stored energy: capacitors in drives can hold a charge after the power is off.
- Damaged cables and fittings: worn insulation, loose terminals, and overloaded sockets.
- Backup power: emergency or rescue batteries can keep circuits live after the main switch is off.
Falls and access
- Openings in the floor: open trap doors can lead to falls.
- Slips, trips, and falls: oil on the floor, loose cables, stored materials, and uneven floor levels.
- Falling objects: tools or parts dropped through a floor opening onto people below.
- Working at height: using ladders or platforms to reach overhead equipment.
- Limited space: tight access around the machine and controller can restrict movement and escape.
Environment
- Heat: motors, brakes, resistors, and drives can be hot, and the room can overheat if ventilation fails.
- Noise: noisy machines can damage hearing and hide warning sounds.
- Fire: oil, grease, rubbish, and stored flammable items.
- Poor lighting: shadows hide hazards and make labels hard to read.
- Unauthorized entry: untrained people may enter and touch equipment.
Controls
Access and Awareness
- Keep clear access to the machine room at all times.
- Keep clear access to the main switch, machine, controller, hand-cranking (manual winding) device, and brake release lever.
- Know the location of the nearest stop switch and the main switch before you start work.
- Keep the machine room door locked, and allow only authorized persons to enter.
- Post warning signs at the entrance, and make sure the door opens easily from the inside.
- Keep the room free of stored materials, rubbish, and anything not needed for the elevator.
- Make sure there is adequate permanent lighting and an emergency light, and carry a torch as a backup.
- Display the elevator layout, wiring diagrams, and emergency procedures where technicians can see them.
- Label the main switches and controllers clearly so each can be matched to the right elevator.
Before You Start Work
- Plan the job and complete a risk assessment before you go in.
- Tell your colleague, supervisor, or building representative where you will be working.
Put “Out of Service” signs at the landings and secure the elevator from the public.- Check that no one is in the car before you take the elevator out of service.
- Wear the required PPE, such as safety shoes, eye protection, and hearing protection where noise is high.
- Remove jewelry and loose items, and tie back long hair.
- Check that your tools and meters are in good condition and rated for the voltage.
- Check the room for oil spills, water leaks, and damaged equipment before you start.
Electrical Safety
- Switch off the power to the relevant elevator before working on any part of it.
- The only exceptions are specific tasks, such as fault finding and some tuning or adjustment, that cannot be done without the equipment energized. Treat these as higher-risk and follow your procedure.
- Remember that control systems may be electrically interconnected, so a circuit may be live even when the elevator you are working on is off.
- Always test an electrical point before touching it.
- Never assume that a safety switch isolates the circuit you are working on. A safety switch is designed to stop the elevator, not to isolate every circuit. Play it safe and switch off the main switch.
- Be aware of live electrical equipment when you carry or use metal items, such as tools, ladders, and tapes, in the machine room.
- 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 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 or battery supplies, such as rescue device batteries and emergency lighting circuits, that may still be live.
- Use insulated tools, and use only one hand for probing where possible.
- Keep your hands, tools, and the floor around electrical panels 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.
- Keep controller and panel doors closed when you are not working on them, and keep the area around panels clear.
- Account for every jumper used, and remove all jumpers before returning the elevator to service.
Rotating Machinery
- Keep guards in place at all times. Remove them only for maintenance, and replace them before you leave.
- Remember that machinery can start unexpectedly and cause injury.
- Do not wear loose-fitting clothing near rotating machines, because it can get caught and pull you in.
- Do not wear gloves when working near moving or rotating machinery.
- Keep your hands, tools, and wiping cloths away from the sheave, ropes, and rotating shafts.
- Never clean, oil, or grease moving parts while the machine is running. Switch off and isolate the elevator first.
- Hold wiping cloths in your palm, and never wrap them around your hand.
- Do not lean on or reach across rotating machinery.
- Wear hearing protection near noisy machines.
Manual Rescue and Brake Release (new)
- Only trained and authorized persons should operate the hand-cranking device or release the brake.
- Switch off the main switch before you use the hand-cranking device.
- Before you move the car by hand, check that all landing doors are closed and that no one is in the shaft.
- Follow the manufacturer’s procedure for releasing the brake, and release it gradually.
- Stay clear of the sheave and handwheel while the car is moving, and be ready for it to move when the brake is released.
- Remove the handwheel and return the equipment to its normal state when you finish.
- Check that the brake works correctly before returning the elevator to service.
Trap Doors and Openings
- If a trapdoor in the machine room floor is opened, erect a guardrail around the opening.
- Do not stand or walk on a trap door.
- Close and secure trap doors when you are not using them, and mark the openings clearly.
- Never leave an open trap door unattended.
- Keep tools and materials away from the edge so they cannot fall through.
- Check that trap doors are in good condition and rated for the loads they carry.
Housekeeping, Fire, and Environment
- Keep the floor clean and dry. Wipe up oil and grease immediately.
- Put oily rags in a covered metal container, and keep flammable materials out of the room.
- Keep a suitable fire extinguisher nearby, check that it is up-to-date, and know how to use it.
- Do not smoke, and keep flames and sparks away from the room.
- Make sure the room is ventilated and the temperature stays within the equipment’s limits. Report a failed fan or air conditioner to building management.
- Be careful of hot surfaces, such as motors, brakes, and resistors.
- Drink water and take breaks in hot conditions.
- Do not use the machine room for storage, and keep the doors closed when you are not present.
Working at Height and Lifting
- Use a stable, rated ladder or platform, and do not overreach.
- Do not use makeshift steps, chairs, or boxes.
- Use mechanical aids or a team lift for heavy parts, such as motors, brakes, and controller components.
- Use only certified lifting equipment, and never stand under a suspended load.
Working Alone and Emergencies
- Avoid lone working where possible. If you must work alone, arrange check-in times and carry a working phone or radio.
- Know the location of the nearest first-aid kit, fire extinguisher, and exit.
- Know how to call for help and how to switch off the power in an emergency.
- If someone suffers an electric shock, switch off the power first if it is safe to do so. Do not touch the person until the supply is off. Then call for medical help.
- If you smell smoke or see fire, stop work, raise the alarm, and evacuate.
- Report every injury, incident, and near miss to your supervisor.
Before Leaving the Machine Room
- Replace all guards and covers, and close the controller and panel doors.
- Remove all jumpers, locks, and tags, and test the safety circuits.
- Take all tools, rags, and materials with you.
- Check that the hand-cranking device and handwheel are in their proper place.
- Close and lock the machine room door.
- Remove “Out of Service” signs, and tell building management what was done.
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