Final answer:
OSHA mandates the use of shoring to prevent surface water from entering an excavation, emphasizing worker safety and hazard elimination as part of maintaining a safe work environment.
Step-by-step explanation:
OSHA requires that shoring or other suitable means be used to prevent surface water from entering an excavation. Shoring involves the use of supports to stabilize trench walls and is a part of OSHA’s regulations to ensure worker safety in excavation sites. One of OSHA's many standards includes the provision of equipment to prevent trenching cave-ins, which is highly relevant to preventing water from entering excavation sites.
Employers are responsible for maintaining a safe work environment, which includes using methods such as shoring to eliminate hazards. Rather than solely relying on personal protective equipment (PPE), which might not be sufficient to handle certain hazards, OSHA stresses using other preventative measures to reduce risks effectively.