Zip ties on scaffolding are commonly utilized for non-structural tasks, like attaching shade cloth inside mesh to prevent falling objects. However, in Queensland, there's a growing trend of using zip ties in structural scaffolding applications, replacing established proprietary components.

Scaffolding manufacturers typically do not endorse the use of zip ties for load-bearing applications, posing risks of falls or objects dropping from heights. Despite load-rated zip ties being available, they are only approved for tensile (pulling) loads, not shear (cutting) loads. Workers might mistakenly assume their adequacy for various scaffolding tasks. Plastic zip ties, unlike proprietary components, lack performance testing for structural scaffolding applications. Instances have shown that zip ties can be cut through by scaffolding plank edges, especially when a worker's foot inadvertently contacts the plank.

In line with the Work Health and Safety Regulation 2011, all prefabricated scaffolding must undergo design registration before use in Queensland. Design registration involves submitting component drawings with the application and verifying the scaffolding design by a competent person, such as a professional engineer, to an appropriate standard (e.g., Australian Standard Plant design verification Scaffolding licenses HWSA – Scaffolding checklist AS/NZS 1576 Scaffolding). Opting for zip ties instead of approved scaffolding fittings likely violates the manufacturer's and design verifier's directions.

The Scaffolding Code of Practice 2021 doesn't provide explicit guidance on zip tie use, but Section 5.7 suggests securing metal planks with rated fixings and avoiding non-structurally rated systems for securing planks on hop-up brackets.

Photographs comparing scaffolding examples using proprietary products and plastic zip ties serve as illustrations of unsuitable applications, although there could be other instances not depicted. It's essential for workers to adhere to manufacturer-approved components and industry standards to ensure safety and regulatory compliance.

Unsafe examples of zip ties

Two and three board hop-up brackets

Install tie bars on all two and three board hop-up brackets to prevent the brackets from spreading apart and causing planks to dislodge.

Note: One board hop ups are generally designed without tie bars.

Lapped planks on hop up brackets

Use proprietary system bolts to secure handrails to stair cases.

Top and mid rails

Non load bearing use of zip ties

In examples 6 and 7 the typical loading applied to the toe board will be directly applied to the scaffolding standards. Please note that while zip ties could be used in this way, the example is unusual.

Note: the cantilever (overhang) should not exceed 300 mm.

Example of zip ties on a toe board where direct loading is not transferred to the zip tie

Same example as example (6) showing maximum cantilever (overhang) of 300 mm.

Example 8 shows a zip tie connecting shade cloth to the inside of steel mesh – as a falling objects control measure. In this example, the zip tie is being used to fasten the shade cloth to the mesh. Any loads applied by materials ejected from the building will be applied directly to the steel mesh and then to the scaffolding tubes. This shows an acceptable use of a zip tie.

Note: Zip ties in this application can be difficult to install. Alternative connectors can be used. One example is a push-on metal clip.

It is crucial to note that, unless explicitly directed otherwise by the scaffolding designer or manufacturer through documented advice, WorkCover Queensland deems the utilization of non-proprietary or non-structurally rated items, like zip ties, unacceptable for structural loading. The rationale behind this stance includes the absence of verification from the modular scaffolding system manufacturer regarding the structural applicability of these components. Additionally, these non-proprietary items are not designed to withstand shear loads, and their rated tensile strength is relatively low. It is essential for workers to adhere to approved and structurally rated products to ensure the safety and integrity of scaffolding structures.