At a trench cave-in, sources of vibration should be eliminated at what distance?

In the context of trench safety, it is crucial to understand the impact of vibrations from nearby activities when a trench is being excavated. Vibrations can destabilize the soil and contribute to the risk of a trench cave-in, which poses significant hazards to workers.

The correct distance for eliminating sources of vibration, specifically at 500 feet, is based on recommendations for ensuring safety in excavation operations. The rationale for this distance is that it allows for ample precaution in removing not only immediate threats but also secondary vibrations that might influence the stability of the trench. This distance can help reduce the potential for soil shifting or collapsing, thereby protecting the workers within the trench.

In addition, the designated distance aligns with established industry standards and safety guidelines, which encourage maintaining a safe working environment in excavation operations. By enforcing a 500-foot buffer zone around the trench, the likelihood of vibrations affecting the soil integrity is minimized, thereby reducing the risk of cave-ins during excavation.

Other distances provided in the options, while they may seem reasonable, either exceed industry recommendations or are not supported by guidelines aimed at maintaining worker safety in excavation settings.