Which of the following is not considered sufficient fall protection for work platforms above six feet?

Warning signs are important for promoting safety consciousness and alerting workers to potential hazards, but they do not physically prevent falls. Instead, effective fall protection systems are designed to either eliminate the risk of a fall or catch a worker should a fall occur.

Guardrails provide a physical barrier that serves to prevent workers from falling off edges or into dangerous areas, making them a reliable form of protection. Safety nets also act as fall arrest systems by catching workers if they fall, thereby significantly mitigating the severity of injuries. Personal protective equipment, such as harnesses and lanyards, helps ensure that workers are tethered and safe while working at height.

In this context, while warning signs can serve as a visual reminder, they do not provide the actual physical protection necessary for safe work practices at or above six feet. This is why warning signs are not deemed sufficient fall protection for elevated work platforms.