SafeWork NSW v Grasso Consulting Engineers Pty Ltd; SafeWork NSW v Ignazio Grasso (2019)
An engineering company and its sole director unsuccessfully defended a work health and safety prosecution for failing to create a computer model to calculate the risk of an unexpected structural collapse, which exposed workers to the risk of death or serious injury.
Grasso Consulting Engineers Pty Ltd (Grasso) was engaged by Hassarati & Co Pty Ltd (Hassarati), a demolition contractor, to provide structural engineering advice services on an ad hoc basis. Grasso had no employees and Mr Ignazio Grasso, the sole director, provided his services as an engineer through the company. Hassarati was contracted by Lendlease Building Pty Ltd (Lendlease), which successfully tendered for the redevelopment of the Darling Square site in Haymarket, where the Sydney Entertainment Centre was located (the premises). Hassarati subcontracted Rosenlund Contractors Pty Ltd (Rosenlund) to demolish the roof of the premises using an excavator. Mr Paul McClutchie and Mr Nigel Hayward were employed by Rosenlund to demolish the roof of the Sydney Entertainment Centre using the excavator.
The demolition involved the operation of the excavator by Mr McClutchie under the supervision and guidance of Mr Hayward, each other in contact by two-way radio.
On 19 March 2016, Mr McClutchie was operating a 70-tonne excavator to remove air-conditioning ducts held up by wire as part of demolishing one of the nine bays, when the bay’s remaining roof structure unexpectedly collapsed and steel trusses fell onto the excavator cabin. In doing so, the excavator cabin was partially crushed and, although not injured, Mr McClutchie was trapped and had to kick out the windscreen and climb out. The excavator was “written-off”.
SafeWork NSW charged Grasso pursuant to section 19(2) of the Work Health and Safety Act 2011 (NSW) (Act) and Mr Grasso pursuant to section 27 of the Act, both with category 2 offences.
Grasso and Mr Grasso unsuccessfully defended the matter. The NSW District Court found that the roof structure was “large and complex and highly unusual”, which constituted a ‘special structure’ under the Demolition Work Code of Practice (DW Code), requiring proper planning and care in accordance with the DW Code.
The Court found that Grasso’s advice that any bay could be demolished in any order is a highly unusual way to proceed with a special structure, and in this case, such advice gave the demolition workers discretion as to the order of demolition of the bays. Grasso’s advice included sketches and plans that were relevant to just two of the bays, which had different structural configurations to the others. The advice was also not clear on which structural members needed to be retained in the other bays during the demolition process and did not provide express instructions in relation to the bay where it collapsed.
The Court found that Grasso failed to comply with its health and safety duty with the following reasons:
- to competently assess the load factor of the structure during its progressive demolition, the use of computer modelling software was necessary and hand calculations were insufficient;
- although Grasso did undertake some engineering analysis, the exercise of engineering judgement alone was potentially fallible as it did not take into account the actual or an assumed load on the structure at various times during the demolition;
- Grasso’s failure to create a computer model meant that it could not test any of the advice it gave against the load factors forecasted by the model to predict the risk of an unplanned structural collapse, which included the advice that the roof structure could be demolished in any order;
- without creating a computer model, Grasso was not in a position to know whether or not its advice may give rise to a risk of unplanned structural collapse, which was obviously a risk to the health and safety of the workers in the vicinity; and
- the preparation of a computer model was a reasonably practicable step that Grasso could have taken, and it failed to eliminate or minimise the risk of an unplanned structural collapse by not undertaking design calculations by way of computer modelling.
The Court found that Mr Grasso failed to comply with his health and safety duty to exercise due diligence for the following reasons:
- Mr Grasso failed to undertake appropriate engineering analysis and design calculations by not creating a computer model;
- Mr Grasso was in a position as a qualified structural engineer to ensure that Grasso took the reasonably practicable step of creating or causing to be created a computer model;
- it was a reasonable step for Mr Grasso to take in exercising due diligence because it was a process available to Grasso to use to eliminate or minimise the risk to health and safety from the work of the company and/or it was a process that could be implemented to comply with the company’s duty; and
- Mr Grasso was in a position as a qualified structural engineer to ensure that the advice given by Grasso was properly considered advice, and that it was based on the undertaking of appropriate engineering analysis and design calculations in the form of a computer model.
As a result, the Court held that Grasso and Mr Grasso were each in breach of their health and safety duties. The Court held that there was a failure to create a computer model to assess the risk of unplanned structural collapse and the Company failed to adequately communicate which structural members were not to be demolished during the demolition. This insufficient communication led to the interpretation that all of the structural members were to be removed from each bay, which was then used to instruct the Rosenlund workers on how the demolition was to be performed. The unequivocal part of Grasso’s advice was that any bay of the roof structure could be demolished in any order and still maintain the structural integrity of the roof. Lendlease, Hassarati and Rosenlund relied on Grasso’s advice.
The Court held that the breach of section 19(2) and section 27 by Grasso and Mr Grasso respectively was a significant or substantial cause of the Rosenlund workers being exposed to a risk of unexpected structural collapse. The Court announced a sentencing hearing would be set at a later date.
When providing advice, a company must ensure that reasonably practicable steps are taken, and sufficient analysis undertaken to minimise and eliminate any risks, which may include creating a computer model for a precise analysis. This case also illustrates the importance of codes of practice, and the steps that must be followed and implemented to control risks.