Safety warning issued as workers injured in formwork collapse

In June 2022, several concreters were injured after falling between three and four metres when a formwork deck collapsed at a construction site. Initial investigations found they were pouring a concrete slab for a mezzanine floor when for reasons yet to be established, the formwork system failed.

Formwork is a temporary structure used to contain and shape wet concrete until it is self-supporting. Once assembled, the components form the temporary structure. Formwork incidents can have serious consequences; hazards associated with formwork erection, alteration or dismantling can include formwork collapse (before, during and after placement of concrete), falls from heights, slips and trips, falling objects, and dust.

Taking steps to manage risks is a condition of doing business in Queensland; effective risk management starts with a commitment to health and safety from those who manage the business. Persons conducting a business or undertaking (PCBUs) are advised to use the hierarchy of controls to help decide how to eliminate and reduce risks in their place of work. The hierarchy of controls ranks types of control methods from the highest level of protection and reliability to the lowest, providing a step-by-step approach to eliminating or reducing risks. PCBUs must work through the hierarchy of controls when managing risks, with the aim of eliminating the hazard, which is the most effective control.

A PCBU must eliminate risks so far as is reasonably practicable, and if it is not reasonably practicable to eliminate the risks, they must minimise those risks. PCBUs must also ensure, so far as is reasonably practicable, the design, provision and maintenance of safe formwork plant and structures; the safe construction, alteration, dismantling and use of formwork; and the safe use, handling, storage and transport of formwork plant.

Eliminating hazards at the design or planning stage is often easier and more cost-effective to achieve then making changes later when hazards become real risks in the workplace. Safe design means the integration of control measures early in the design process to eliminate or minimise the risks to health and safety throughout the life of the structure being designed.

A suitably qualified civil engineer experienced in formwork design is responsible for overseeing the safe design and certification of the complete formwork structure. This includes design of the formwork structure, the formwork deck and connection details, and certification that the formwork drawings and other formwork documentation have been completed. When specifying the design of the formwork system, the engineer must allow for all loads that can be expected to be applied during construction, including loads applied by the formwork deck, supporting members and formwork frames; any false decks that may be provided; concrete pouring techniques; the concrete pour which includes both the weight of the concrete and dynamic factors applied; workers on the formwork deck and false decks; stacked materials; crane lifted materials on both the complete and incomplete formwork deck; and environmental loads including forces due to water flowing around the formwork.

PCBUs must implement a range of control measures for potential formwork issues. They must determine where floors to be poured are supported by welded steel brackets, ensure that the bracket design has adequate strength and that the welding and material specifications comply with the design engineer’s instructions. PCBUs must complete all formwork documentation in accordance with the Formwork code of practice 2016. This includes all project and formwork engineer drawings, specifications and engineer certifications; all pre-pour inspections, formwork systems and associated components, and site erection methods; and the engineer or competent person sign-offs.

All modular proprietary formwork systems must be constructed in specific configurations, as prescribed by the designer and manufacturer. Both modular and traditional formwork systems should be designed to comply with the loadings and general principles of AS3610: Formwork for Concrete. PCBUs must also ensure that all materials and equipment used in formwork construction must be fit for the intended purpose and meet design specifications. Further, the design of materials and equipment must conform to relevant Australian Standards and must also be manufactured in accordance with a quality assurance system that ensures compliance with the design specification. A suitable system must be implemented to ensure that only materials and components that comply with the specifications of the formwork design drawings and documentation are being used. Materials and components that are damaged or not fit for the intended use must not be used; this includes broken components, timbers with rot or excessive nail holes, and components with missing parts.

PCBUs are also responsible for ensuring that clear access is provided for the safe movement of materials, equipment and persons onsite. To that end, designated access ways must be provided, and emergency access and egress must be considered and provided to all parts of the workplace where persons are required to work. Two forms of emergency access and egress should be maintained at all times. When possible, stretcher stairs should be the primary access to the formwork deck.

Workers and health and safety representatives are required to be consulted at each step of the risk management process. Workers must also be consulted as formwork activities begin. Where PCBUs share responsibility for a health and safety matter with other business operators who are involved in the same activities or who share the same workplace, they must exchange information to find out who is doing what and work together in a cooperative and coordinated way so that all risks are eliminated or minimised as far as reasonably practicable.

Workers must receive all relevant training, information and supervision relating to the system they are constructing, including specific training for formwork systems. Such training and information should include, but not be limited to, the formwork system, tasks, activities and components; the way the manufacturer or designer of the formwork system intended the system to be constructed, installed, used, moved, altered or dismantled; specific training and information required to undertake or participate in specific tasks or activities; and safe work procedures, including the use of mechanical aids and devices, where appropriate.

PCBUs must also train workers on using and maintaining equipment, including any specific conditions and prohibitions on the use of equipment. They must also be aware of any personal protective equipment required, with instruction in fitting, use, cleaning, maintaining and storing the equipment. The training must also address emergency procedures, including persons with specific emergency roles and responsibilities.

A Safe Work Method Statement (SWMS) may also be needed, as formwork could include construction work that is defined as high-risk construction work in the WHS Regulation. In these instances, a SWMS must be prepared before the work starts. PCBUs are also advised to consult with formworkers and other workers, prior to sign-off and handover. Edge protection should be implemented, penetrations covered, safe access provided and a formwork zone set up to separate workers. The formwork zone must also be large enough to ensure that these other persons are separated from formworkers.

The control measures put in place should be reviewed regularly to ensure they work as intended.

Image credit: iStock.com/Avalon_Studio