A critical lift is a crane lift with higher-than-normal risk that requires a detailed, written lift plan and review before it happens. Definitions vary by company and site, but lifts are commonly treated as critical when the load is near the crane's rated capacity (often a set percentage of the chart), when two or more cranes lift together, when the load passes over occupied areas or live equipment, when the load is hard to replace, or when conditions are unusual. A lift plan documents load weight, crane configuration, radius, rigging, ground bearing, and responsibilities.
No crane lift should happen without a plan. But the level of planning scales with risk, and most companies draw a line between routine picks and critical lifts, the ones that need a detailed written plan, extra review, and sign-off before the load leaves the ground.
What is considered a critical lift?
There isn't one universal definition. Owners, contractors, and crane companies set their own criteria in their lifting procedures, and project specifications often add requirements. Common triggers include:
- Near capacity: the total load is above a set percentage of the crane's rated capacity at that radius and configuration.
- Multiple cranes: tandem or multi-crane lifts, where load sharing between cranes has to be controlled.
- Over people or live equipment: lifts over occupied buildings, operating plant, energized equipment, roads, or rail.
- Irreplaceable or high-value loads: equipment with long lead times or catastrophic consequences if damaged.
- Unusual conditions: personnel platforms, lifts near power lines, blind picks, unusual rigging, or poor ground.
- Special rigging: custom lifting beams, load rotation or upending, or loads with uncertain centers of gravity.
If your site or client has a definition, follow it. If not, the rigging contractor's procedure should state one clearly.
What goes into a crane lift plan?
Core elements of a lift plan
- Total load weight — the equipment plus hook block, slings, shackles, spreader bars, and any lifting beam
- Center of gravity and pick points
- Crane configuration — boom length, counterweight, outrigger setup
- Radius at pick, at the worst point of the swing, and at set, with chart capacity at each
- Rigging — sling types, capacities, and angles, plus hardware ratings
- Ground bearing — outrigger loads and the mats or cribbing that spread them
- Hazards — power lines, structures, swing path, and exclusion zones
- Weather limits, especially wind
- Communication — signal person, radio channels, and stop-work authority
- Roles and sign-off — who prepared, reviewed, and approved the plan
Why is total load weight more than the equipment weight?
Because the crane lifts everything below the boom tip. The hook block, slings, shackles, and spreader bar can add meaningful weight, and on a lift near capacity that difference matters. A good plan adds them up explicitly instead of rounding the equipment weight and hoping.
How do radius and ground conditions affect a lift?
Crane capacity drops as radius increases. A crane that easily lifts a load close in may not lift it at the setting position across a roof. That's why plans check capacity at every point of the lift, not just at the pick.
Ground conditions matter just as much. Outriggers concentrate large forces into small areas. Soft soil, backfilled trenches, basements, and underground utilities can fail under those loads. Mats and cribbing spread the load, and the plan should show the ground can carry it.
Who approves a critical lift plan?
Approval depends on the company and project. Typically the plan is prepared by the lift supervisor or rigging engineer and reviewed by the crane company, the rigging contractor, and the site owner or general contractor. On complex lifts, engineering review is often required. Everyone who has a role on lift day should see the plan in a pre-lift meeting.
What happens on lift day?
- Pre-lift meeting: walk through the plan, roles, signals, and stop-work rules.
- Verify the setup matches the plan: crane configuration, mats, and exclusion zone.
- Check weather against the limits.
- Inspect rigging before it's attached.
- Make a test lift a short distance off the ground to confirm balance and capacity.
- Execute the lift under one signal person, with taglines controlling the load.
Bottom line
- Critical lifts are higher-risk picks that need detailed written plans and review.
- Common triggers: near capacity, multiple cranes, lifts over people or live equipment, high-value loads.
- A real plan covers total weight, radius, rigging, ground bearing, hazards, weather, and sign-off.
Planning a heavy or critical pick? See our crane and rigging services, or jacking and skidding when a crane isn't the right tool.