This safety alert is published following the death of two workers who were working from a suspended scaffold, which collapsed at a Gold Coast building site in Queensland.
While an investigation is still underway to establish the cause, the incident serves as a tragic reminder that any failure of a suspended scaffold or its support system is potentially catastrophic and the scaffold relies on all of its components, the correct installation and usage to ensure the safety of persons in, or in the vicinity, of suspended scaffolding.
OCCUPATIONAL HEALTH AND SAFETY REQUIREMENTS
The Occupational Health and Safety Act 2000 (OHS Act) requires employers to provide plant and systems of work that are safe and without risks to health, and to provide such information, instruction, training and supervision to ensure the employee’s health and safety at work.
The following control measures relate to suspended scaffolds supported by counterweighted suspension rigs:
- the counterweight provided should be adequate for at least three times the maximum rope tension in the support rope, taking into account the inboard and outboard projections of the suspension rig (Australian Standard AS/NZS 1576. 4 Scaffolding Part 4: Suspended Scaffolding). The maximum rope tension is usually made up of:
- the maximum pull of the scaffold hoist, ie the stall torque or the load-limiter setting if load limited. (for electric winches the load should be limited to 1.25 x rated capacity).
- The weight of the rope(s) attached to the suspension rig
- The stabilising weights attached to the rope(s)
- the suspension rigs, or needles, should be designed by a competent person to support the maximum rope tension at the given outboard, including adequate lateral stability (AS 1576.4).
- the counterweights should be fixed to the suspension rig to prevent them becoming dislodged or removed without the use of a tool.
- the winch ropes and other components should be inspected prior to installation.
- a single rope protective device, or a second rope, to hold the scaffold in the event of a winch malfunction should be provided or incorporated into each scaffold hoist.
- the scaffold should be installed by persons holding an Advanced Scaffolding, or Advanced Rigging Certificate of competency who are competent in the installation of suspended scaffolds of the type being installed, and a handover certificate provided on completion.
- the scaffold should be clearly marked with its rated capacity (SWL) and should not be overloaded.
- Employers must ensure that suspended scaffolding is inspected by a competent person before its first use, before its next use after an occurrence which might reasonably be expected to affect its stability or adequacy, before use following repairs and at intervals not exceeding 30 days.
- operators should check the scaffold, including the suspension rig, prior to each days use to check for any obvious damage or missing counterweights. Note: operators should be provided with sufficient information to enable them to perform that check, or alternatively have the check performed by another competent person.
Further information regarding suspended scaffolds can be found in:
- Australian Standards AS 1567.4: Scaffolding Part 4: Suspended scaffolding and AS 4576 Guidelines for scaffolding
- WorkCover Rigging Guide
More information is also available at www.workcover.nsw.gov.au of from the WorkCover Assistance Service on 13 10 50