According to OSHA, which grounding method is required?

The required grounding method according to OSHA is equipotential grounding. This method is essential for ensuring safety in environments where workers may be exposed to electrical hazards. Equipotential grounding minimizes the potential difference between conductive surfaces, which significantly reduces the risk of electric shock. By maintaining all metal parts at the same electrical potential, the likelihood of harmful voltage differences is diminished, protecting workers from injury.

Equipotential grounding is particularly important in areas where employees are working with or near high-voltage equipment, as it creates a safer working environment by ensuring that fault currents are safely directed away from people and equipment. This method aligns with OSHA's overarching goal of ensuring workplace safety and health.

Other grounding methods, such as phase-to-common, single point, and multiphase grounding, while useful in certain electrical systems, do not prioritize the reduction of potential differences in the same way that equipotential grounding does. Each of those methods may serve specific purposes within electrical systems but fall short of the safety emphasis that equipotential grounding provides in the context of electrical safety regulations set forth by OSHA.