Shoring of a trench excavation prevents which hazards?

• A. Hazardous Atmospheres
• B. Mobile Equipment Incidents
• C. Falling Loads
• D. Cave-Ins

Answer: (D)

Shoring provides temporary support to the sides of a trench so earth pressure cannot push the walls inward and bury workers. By holding the trench walls in place, it directly prevents a cave-in, which is the primary hazard shoring is designed to stop.

Hazardous atmospheres come from gases or lack of oxygen and are managed with testing, ventilation, and atmospheric controls, not wall support. Mobile equipment incidents involve vehicles or equipment around the trench and are mitigated with barriers, spotters, and safe traffic controls. Falling loads refer to materials or equipment overhead; protecting against that requires overhead protection or exclusion zones, not just shoring of the trench walls. So the protection shoring provides is specifically to prevent cave-ins.