In September 2018, a worker received serious head, back and chest injuries while attempting to jump off a trestle to avoid the collapse of a 2.8 metre high block wall. He and another worker who was not injured were constructing the block wall.
In August 2018, a five metre high core filled block wall collapsed at a separate construction site, although in this case there were no injuries.
Investigations are continuing into both incidents.
Preventing a similar incident
During construction, masonry walls (brick or block) can fail due to side loads on the walls, the rate of construction, inadequate foundations or adjacent excavations. Side loads may include wind, inadvertent impact with the walls or leaning materials against them.
Principal contractors and masonry contractors are jointly responsible for the masonry work on the site. As part of the preparation contractors should ensure to provide:
- advice about who is responsible for installing, inspecting and removing any temporary supports
- designs and materials for temporary supports, considering the particular walls' characteristics (seek engineering advice if necessary)
- materials to identify no-go zones – e.g. fencing, tape or signage
- instruction for workers, including site induction and supervision.
Principal contractors and masonry contractors are also jointly responsible for the development of a risk assessment, which should identify any walls that may need temporary supports during construction work. In addition to your risk assessment, an ongoing inspection program should be established. At the start of each day and after any adverse weather conditions, the walls and any temporary supports should be inspected for damage.
Risk assessments may identify a range of control measures including:
- designing walls to provide additional stability during the construction phase, such as adding sequential core filling with reinforcing or wall stiffeners
- installing temporary supports
- establishing stop heights to allow mortar to gain adequate strength before further construction – e.g. at lintel\height
- stacking materials away from unsupported masonry walls – do not lean materials against walls
- preventing inadvertent impact on walls by plant such as wheelbarrows, cranes or pallet trolleys
- monitoring weather conditions such as wind and amending work practices to suit
- installing no-go zones, identified by barricades or other physical identifiers, to keep people outside of potential collapse zones.
Each year there are around 40 accepted workers' compensation claims involving a worker being hit by a falling object. Of these claims, more than a third involve a serious injury with five days or more off work.
Since 2013, there have been 30 notified incidents involving injuries by wall collapses, mostly in the construction industry. In the same period, 29 improvement notices and 33 prohibition notices were issued relating to being hit by falling objects (involving walls).
Prosecutions and compliance
These prosecutions relate to the collapse of a structure, but not block masonry walls.
In 2016, a company was fined $20,000 after two workers were injured when a suspended concrete slab being poured collapsed at a construction site. The workers fell approximately 4.5m along with concrete slurry and formwork. The workers were pouring concrete into the formwork when it gave way. The suspended slab failed because the distance of the span exceeded the distance for unsupported formwork. There was no design signed-off by the engineer or formwork designer.
In 2013, a company was fined $50,000 when a worker's leg and two fingers were crushed. The worker was cutting walls and roof sections at a demolition site. Two walls had been cut and one of them removed, which left an unstable section of the roof. When the worker completed the last cut, this section fell onto him.
- How to manage work health and safety risks Code of Practice 2011 (PDF, 1.02 MB)
- Working at Heights, Construction – WHSQ Guidance
- Managing the risks of falls at workplaces Code of Practice 2018 (PDF, 2.31 MB)
- Masonry wall safety during construction work (PDF, 0.87 MB)