Which of the following is an acceptable material for a guardrail?

A guardrail is a crucial safety feature on scaffolding, designed to prevent falls and enhance workplace safety. The use of scaffold tube as a guardrail material is acceptable due to its strength and durability. Scaffold tubes are specifically manufactured to withstand various loads and impacts, making them reliable for use in scaffolding structures. They can be easily secured and positioned at the appropriate height to comply with safety regulations.

While other materials such as wooden planks might seem sturdy, they can be less reliable due to potential defects or warping over time. Plastic sheeting and cloth netting do not provide the necessary rigidity and strength required for effective fall prevention, making them inappropriate choices for guardrails. The selected option of scaffold tube ensures that the guardrail will maintain structural integrity and effectively safeguard workers against falls.