A young man almost lost his life recently when performing abseil work on a high rise building in the Brisbane CBD.
The worker was part of a team of professional abseil specialists who access the facade of buildings by connecting to anchor points installed on the building’s roof. The building owner had contracted a Brisbane company to install and certify the anchors for the upcoming project. The anchor points - which were part of a surface-mounted anchor and rated to 15kN – visually appeared fine. The young man was about to attach when his supervisor stopped the operation and requested further information about the anchor points and how they had been installed.
Upon further investigation, it was discovered that the building had been re-roofed using a technique where a second roof or 'skin' is installed directly over the existing roof sheeting. This cuts down on cost and installation time compared to removing the old roof first. However, second 'skins' such as that one are not suitable for attaching anchor points to unless they have been properly tied into the original structure and certified by an engineer.
The height safety installation company did not know this and mistakenly installed the anchors under the assumption that it was a standard roof. Believing they had secured the anchor into the structural purlin, they certified the anchor as compliant and safe. In reality, the fixing screws were only screwed into the roof sheeting. When put under load, the chance of this anchor point failing was extremely high.
While no one was hurt, this near miss raises two important questions.
- Who was ultimately responsible for ensuring that the anchor point was safe?
- How can this situation be avoided?
Under the Work Health & Safety Act 2011, all parties involved had a primary duty of care. This duty cannot be transferred and more than one person or company can hold the same duty at the same time, each with a responsibility to ensure they comply with that duty. In this example, the building owner, the height safety installation company and the abseil company all jointly held a duty to ensure the workplace was free of hazards that may affect the safety of workers and others.
This raises the question as to how the building owner and abseil company can ensure that the height safety company has installed the anchors correctly and avoid this situation.
This starts with the building owner choosing a height safety company who asks the right questions. When designing a height safety system the following questions should be answered at the very start:
- What is the roof material? i.e. colourbond etc.
- What is the structure underneath the roof material?
- Have any modifications been made to the roof?
- What is the anchor to be used for? i.e. abseil or fall arrest
- Has that anchor been tested on that type of roof material according to AS5532?
If the above questions are asked and answered at the design stage, issues like the above example can be avoided.