Safe overhead crane operation comes down to five golden rules: never exceed the safe working load (SWL), inspect the equipment before every use, never move a load over people, lift vertically without side-pulling or dragging, and communicate clearly before and during the lift. The practical tips below support these rules in daily work.
The 5 Golden Rules
1. Never Exceed the SWL
The SWL (or WLL, working load limit) is the maximum load the manufacturer defines as safe, shown on the crane, hoist and every sling.
- Know the SWL of the crane, hoist and every sling you use.
- The SWL of the whole system equals the SWL of its weakest component.
- If the weight of the load is unknown, weigh it before lifting.
- No exceptions, not even for “just one lift”.
2. Inspect Before Every Use
Check the brake, hook, wire rope or chain, and safety devices before operating. If anything is abnormal, fix it before work starts.
| Item | What to check |
|---|---|
| Hook | No cracks or bending; safety latch closes fully |
| Wire rope / chain | No broken wires, rust or kinks |
| Sling | Not cut or torn; capacity tag legible |
| Limit switch | Stops the hoist at the upper limit |
| Brake | Holds the load without slipping |
| Controls | Every button works normally |
3. Never Lift Loads Over People
Even a light load can be fatal if it falls. Give a warning before lifting, wait until the area is clear, and use a tag line to guide the load instead of holding it by hand.
4. Lift Vertically: No Side Pulling or Dragging
Hoists and slings are designed for vertical lifting. Side pulling or dragging overloads slings through the angle, bends hooks and puts sideways force on the hoist structure. Before lifting, make sure the chain or rope hangs vertically.
5. Communicate Clearly
Signals must be clear and follow regulations. When several people are involved, only one person gives the commands. Stop and emergency-stop signals must be obeyed immediately, whoever gives them. If a signal is unclear, stop.
Practical Tips for Daily Operation
- Before switching off the power supply, confirm that nobody is around the crane.
- After a sudden power cut, switch the controls off; before resuming, check that the crane works normally.
- During maintenance, disconnect the main power supply and tag or lock it out. Report any fault that cannot yet be fixed to the supervisor.
- Protect ropes and chains with padding where they pass over sharp corners of the load.
- When rotating a load, keep the change in the centre of gravity steady to avoid unintended movement.
- Before anyone goes under a suspended load, agree it with the crane operator and use supporting equipment.
Frequently Asked Questions
What is the most important overhead crane safety rule?
Never exceed the SWL. Every other rule assumes the load is within the rated capacity of the weakest component.
Who should give signals to the crane operator?
One designated person only, using standard signals. Anyone may give a stop signal, and it must be obeyed at once.
Safe operation starts with trained people. See crane operator training and our after-sale service, or contact ONVALLA.
