ISO 12480-4:2008 Jib Crane Safe Use Standard Interpretation
ISO 12480-4:2008 "Cranes — Safe Use — Part 4: Jib Cranes" is the governing standard for the safe operation of jib cranes. It sets out safety operating procedures for portal base, mast, deck, and floating cranes, covering pre-operation inspections, hazard control, and emergency response to ensure that every lifting operation remains safe and controllable from start to finish.
Pre-Operation Safety Preparation
Before each shift, the following safety preparation steps are mandatory. Daily inspections are carried out in accordance with ISO 9927-4 and include a visual check of the portal base structure, boom and mast deformation, hoisting and luffing wire rope for wear and wire breaks, lifting spreader condition, a self-test of the load moment limiter (LML), and a cross-check of the anemometer reading. The work area must also be inspected: the crane rail foundation or floating vessel mooring condition is verified, the working radius is confirmed clear of obstructions and unauthorized personnel, and the anemometer reading must be within the allowable working wind speed limit of ≤20 m/s for portal base and mast cranes. A pre-shift safety meeting is led by the shift supervisor or appointed signaller to brief the crew on the day's lifting plan, load handling schedule, and identified risk points. A trial lift is then performed: the suspended load is raised 200 mm above the ground and held for at least 30 seconds to confirm that the brake holds without slippage, the wire rope spools evenly, and the load remains stable — brake drop must not exceed 10 mm. Kelude jib cranes come fully equipped with a complete set of safety devices.
Safe Operation Requirements During Lifting
Hoisting and luffing on a jib crane must be performed smoothly: hoisting acceleration ≤0.5 m/s², derricking speed ≤0.5 m/min, and slewing must be steady and uniform with acceleration ≤0.1 rad/s² to prevent the suspended load from swinging. The load must remain within the operator's line of sight at all times; where blind spots exist, a signaller or camera assist is required. When wind force reaches Beaufort 4 (5.5 m/s) and the load has a large wind-catching area, a dedicated lifting plan is required; lifting is prohibited at Beaufort 6 (10.8 m/s) or above. For multi-crane coordinated operations, each crane's load must not exceed 75% of its rated capacity, with a single commander coordinating the lift and a safe distance of at least 1.2 times the sum of the maximum working radii of all cranes involved. After each lift, the boom is lowered to a safe angle; in non-working condition, it is stowed at minimum radius or at the designated anchoring position.
| Safety Elements | requirements | Control Measures |
|---|---|---|
| Wind Speed | ≤20m/s Portal base | Anemometer Alarm & Stop |
| Trial Lift | 200mm/30s | Braking Load Drift≤10mm |
| Multi-Crane Operation | ≤75%+safe distance | Special Plan Commander |
| Slewing | ≤0.1rad/s² | Smooth Operation |
| special working conditions | Heavy Load in High Wind | Special Lifting Plan |
Post-Operation Procedures and Shift Handover
At the end of each shift, carry out the following steps: lower the boom to its minimum working radius or the designated anchoring angle, raise the hook to at least 2 m below the boom tip, and detach the lifting spreader. Shut down the engine or disconnect the main power supply, then lock the operator cabin doors and windows to prevent unauthorized access. Record the shift's activities in the operation log, including the type of work performed, number of hoisting cycles, maximum load lifted, and any abnormal conditions. During shift handover, both outgoing and incoming operators conduct a joint routine inspection, with particular attention to areas where abnormal operation or overload events were logged. Both parties sign the operation log to confirm the handover. If the crane has been idle for 3 or more consecutive days, perform a full daily inspection before returning it to service. Kelude jib cranes are equipped with safety devices in full compliance with ISO 12480-4:2008.
| Item | Description | Responsible Person |
|---|---|---|
| Boom | Lower To Minimum radiusanchoring | Operator |
| Hook | Raise to Clear Boom Tip≥2mUnload Lifting spreader | Operator |
| Power Supply | Main Power Offcontrol circuit | Operator |
| Leave Crane | Lock Cab | Operator |
| Handover | Combined Operationdaily inspection+Log Sign-off | Both Parties |
FAQ: Crane Safety, Wind Limits & Daily Inspections
Q: What does the pre-shift safety preparation involve?
A: Daily inspection per ISO 9927 Cranes — Inspections, site check for obstacles (working wind speed ≤20m/s), a pre-shift safety briefing on risk points, and a trial lift to 200mm held for 30s with braking descent limited to ≤10mm.
Q: What are the wind speed limits for boom operations?
A: Working wind speed must not exceed 20m/s for portal base and mast cranes, and 15m/s for floating cranes. A dedicated plan is required for heavy lifts in Beaufort scale 4 winds, and hoisting must stop in scale 6 winds. Anemometers provide real-time monitoring.
Q: How do multiple cranes work together safely?
A: A dedicated lift plan is required, with each crane limited to 75% of its rated capacity under a single coordinator. Safe distance between cranes must be at least the working radius plus 1.2 times the suspended load. Contact between booms or loads is strictly prohibited.
Q: What is the procedure after completing lifting operations?
A: Anchor the boom, raise the hook to at least 2m, cut the power supply, lock the cabin, and log the operation. Conduct a handover with daily inspection and sign-off. If the crane is idle for 3 or more days, perform a full daily inspection before the next use.
