Mobile Hydraulic Cranes

Mobile hydraulic cranes (truck, rough-terrain and all-terrain cranes) lift loads with a telescoping boom, powered by hydraulic cylinders. They are quick to set up and found on almost every construction site. They also account for many crane deaths: tip-overs, power line contact, struck-by loads and boom failures follow from poor setup, overloading and bad planning.

• Crane Operators
• Riggers
• Signal Persons
• Lift Directors
• Contractors

Types

• Truck-mounted cranes: a crane on a truck chassis, driven on roads, set up on outriggers.
• Rough-terrain cranes: four-wheel drive, short wheelbase, for job sites; usually set on outriggers.
• All-terrain cranes: multi-axle, road legal and off-road capable, with long booms and heavy capacity.
• Boom trucks and knuckle-boom cranes (lifting material from delivery trucks). See Boom Trucks.

OSHA basics

In construction, cranes are covered by OSHA's Cranes and Derricks standard (29 CFR 1926 Subpart CC). Key points include:

• Operators must be qualified or certified and evaluated for the equipment they operate. See Crane Basics.
• A competent person must inspect the crane: before each shift, monthly and annually (with documentation as required). See Crane Inspections.
• Signal persons and riggers must be qualified. See Signal Person Qualification and Qualified Riggers.
• The employer must follow the manufacturer's procedures and have the load chart in the cab. See Load Charts.
• For assembly and disassembly, a competent and qualified person must direct the work.
• Power line rules: the crane must keep a safe distance (generally at least 20 feet for lines up to 350 kV) unless other measures are used. See Cranes & Power Lines.

Planning the lift

• Have a lift plan for every lift, and a critical lift plan for heavy, complex or sensitive ones. See Lift Planning.
• Know the load weight including rigging, hooks, blocks and attachments, and the radius at which it will be lifted. See Estimating Load Weight.
• Choose the crane configuration (boom length, jib, counterweight and outrigger position) that matches the load chart for the lift, with a margin of capacity.
• Walk the site: ground conditions, underground voids and utilities, overhead lines, slopes, obstructions and traffic. Locate sewer lines and tanks under the crane.
• Check wind and weather limits from the manual. See Lift Wind Limits.
• Plan the swing radius and exclusion zones to keep workers out of the swing and out from under the load. Barricade the area.

Setup

• Set up on firm, level ground within the manufacturer's limits (usually 1 percent). Use outrigger pads or cribbing sized for the ground bearing pressure, and verify the ground can take the load. See Crane Setup.
• Fully extend and set the outriggers as the load chart requires, with all tires off the ground (when the chart calls for it). Use the outrigger beams and floats in the right positions.
• Make sure the crane is level and check the level indicator. Re-check after loading and as ground settles, especially after rain.
• Set the load moment indicator (LMI) or computer for the actual configuration and verify it works. Don't bypass or override safety devices. See Crane Safety Devices.
• Check hoist cables, hooks, latches, anti-two-block, boom angle indicator and alarms. Check the swing brake and travel lock.

During the lift

• Use clear signals, radio or hand, from one qualified signal person. Everyone obeys a stop signal from anyone. See Crane Hand Signals and Radio Signals.
• Test-lift the load a few inches to check balance, rigging and brakes before lifting higher.
• Lift smoothly, avoiding jerks, sudden stops and side loading. Keep loads close to the crane and below the boom tip clearance.
• Never lift over people and keep everyone out from under the load. Use tag lines to control swing, not hands on the load. See Rigging Basics.
• Never exceed the load chart, including for pick-and-carry. Account for wind, boom deflection and dynamic effects.
• Don't leave the operator's seat with a suspended load, and don't use the crane to drag, pull or drag loads sideways. Keep the cab free of distractions. See Blind Lifts.
• Don't lift personnel with a hook unless the strict personnel lifting rules are met. See Hoisting Personnel.
• When the lift is finished, retract and stow the boom, set the swing lock and secure the crane.

Traveling and moving

• Follow the manual for travel with a load, if allowed, with the boom low and aligned and speeds slow. Avoid slopes and soft ground.
• Watch overhead and underground hazards, bridges, culverts, overhead lines and low clearances when moving.
• When driving on public roads, follow the traffic laws, axle weight rules and permits. See Oversize Loads.

Mobile crane checklist

• The operator is qualified, the crane is inspected and the load chart is in the cab
• I know the load weight and radius, and the lift plan is in place
• The crane is level on firm ground with outriggers fully set on pads
• Power lines are located and clearance is maintained; a spotter is used if needed
• A qualified signal person and rigger are in place; nobody is under the load

Last updated: October 5, 2026