Hiring a mobile crane
Some jobs on a building site need a load lifted that no one can move by hand.
In the UK a mobile crane can be hired in two ways, and they put the responsibility for the lift in different places.
These notes explain the difference, and what the firm hiring the crane has to do either way.
Crane hire or contract lift
The Construction Plant-hire Association (CPA) describes the two kinds of contract. The British Standard BS 7121 sets out which one a firm should choose.
Under a crane hire, the supplier provides the crane and a competent operator. The firm hiring it plans and supervises the lift. Under the CPA's model conditions, that firm answers for everything to do with the crane, including the acts of the operator and rigging team.
Under a contract lift, the crane supplier plans, supervises and carries out the lift.
Which one fits the job
Every lift must be planned in advance by someone with the knowledge and experience to plan and manage it. The CPA's guidance is plain about the choice. A firm that cannot plan and manage the lift itself should choose a contract lift.
Under a crane hire, the lift is planned by the hiring firm's own Appointed Person. Even then, the firm keeps responsibility for the lifting operation.
The CPA suggests talking to more than one supplier. It also suggests seeing evidence of the operators' training, and checking that an independent body carries out the crane's thorough examinations.
Keeping a contract lift clear
On a contract lift, the hiring firm should not push its own plans or staff onto the crane supplier. When both sides share the work, it can become unclear who was in control if something goes wrong. The CPA calls this a hybrid lift, and BS 7121 rules it out.
If the hiring firm does take a part, such as the final positioning of a load, it should be agreed in advance. Everyone should know who does what, and when control passes from one to the other.
The ground is the hirer's job
Under either contract, assessing and preparing the ground stays with the firm hiring the crane. It controls the site and can bring in the expertise to assess the ground.
The supplier should give accurate loadings for the crane's outriggers. The hirer then has to establish what the ground, structure or buried services can bear. Larger crane pads can spread the load where the ground needs it. The hirer also owes the supplier enough detail about the load for a proper lift plan.
Planning the lift safely
The Health and Safety Executive (HSE) publishes guidance on the Lifting Operations and Lifting Equipment Regulations 1998, known as LOLER. It asks for a plan in proportion to the risk.
The crane should be placed to keep lifting over people to a minimum. It should also stay clear of overhead power lines, nearby trenches and buried services such as drains. Where a load hangs for a long time, the area beneath it becomes a danger zone, and people are kept out.
Cranes near airfields
The Civil Aviation Authority (CAA) says the firm hiring the crane is responsible for telling nearby airfields and for lighting the crane. Notice is needed for a crane within 6km of an airfield that rises above 10m or the surrounding buildings and trees.
Any crane of 100m or more must be notified to the CAA wherever it stands. For planned projects the CAA asks for at least eight weeks' notice.