In recent times, camera systems are increasingly being installed on tower cranes to assist the crane operator with the safe lifting of loads. Installing cameras assists the operator with visibility and aims to prevent dangerous situations that could potentially occur during lifting.
Whilst the use of camera on tower cranes can be beneficial, cameras must not be seen as a replacement for a qualified signaller. Cameras should be used in conjunction with and as an aid to good communication between the tower crane operator and signaller.
The Tower Crane Interest Group of the Construction Plant Hire Association (CPA) recently published new technical information notes regarding camera systems on tower cranes.
The technical notes cover a wide selection of information regarding the setting up, maintenance and use of cameras on tower cranes.
Camera mounting positions for different types of tower crane
Cameras can be attached to the tower cranes in various positions, with the three most common positions being hook block mounted, trolley mounted and jib mounted.
Hook block mounted cameras – Suitable for all crane types
Advantages of the hook block mounted positioning of the camera are that a zoom lens is not required to see the load below, it provides a view from above and the camera can be accessed at ground level.
Disadvantages of this positioning include making the camera sensitive to windy conditions, the size of the load may obscure the view of the camera and also the need to recharge the battery packs which power the camera and wireless equipment needed to operate the camera.
Trolley mounted cameras – Suitable for Flat Top and Saddle Cranes
Advantages of the trolley mounted positioning of the camera include the ability to install the camera in a position where it is unlikely to struck or damaged, solar power is able to power the camera and the view is not sensitive to hook block rotation or the wind.
Some disadvantages can include the potential need for a zoom lens to be able to see loads accurately on taller tower cranes and the need for an inspection basket to also be installed for the camera or access and maintenance of the camera may not be possible.
Jib mounted cameras – Suitable for Luffing Cranes
The jib mounted positioning of the camera advantages are that power can come both from solar and hardwired means, it is unlikely to be struck or damaged and the view will cover the load, the hook block, hoist rope and lifting accessories.
As with trolley mounted, the jib mounted positioning may require a zoom lens on taller cranes and will likely require an inspection basket to be installed for maintenance and access – jib mounted also requires a pivot mechanism to be installed so the view is not obscured when the jib angle is altered.
In the crane cab, the camera monitor should not restrict the operator’s direct line of sight or impede any controls. The monitor should be able to be seen in direct sunlight.
Installation of Camera Systems
Cameras systems and their components should be fastened to the crane securely to lower the chance of anything falling from the crane and causing damage or injury. When a camera is installed using magnets, extra security tethers should also be installed as a backup.
Tethers should be fastened to suitable anchor points, should be able to take twice the weight of the item that is being secured and should be as short as possible to lower the chance of snags or contact with other parts of the crane. Any carabiners used should be double action locking and for outdoor use.
Maintenance and Inspection of Camera Systems
Any cameras installed on tower cranes should be inspected to confirm the camera is working as intended, that the camera, batteries and associated parts are secure and there is no damage to cables, connectors and security tethers.
The frequency and responsibilities of the inspections and maintenance varying depending on the positioning of the camera. Information regarding frequency and responsibility can be found in the new technical information notes.
During investigation to any workplace incidents, having recordings can be extremely beneficial and can aid in preventing reoccurrences by being be utilised during training.
The ability to record video and voice communications from camera mounted to a tower crane is recommended. Any recordings should be accessible in a common format and should be securely stored and protected against accidental deletion or corruption.
All operators and signallers must be aware if they are being recorded and proper signage making all involved on site aware that they are being recorded should be provided.