Which safety precaution is critical when working with electrical systems?

When working with electrical systems, de-energizing circuits is a critical safety precaution because it effectively eliminates the risk of electric shock or accidental electrical discharge while performing maintenance or installation tasks. By ensuring that the circuits are completely powered down, workers can safely handle wires, connections, and components without the danger posed by live electrical current. This step is foundational in maintaining safety standards and protocols within electrical work environments.

Other safety measures, such as wearing rubber gloves, can enhance personal protection; however, they do not substitute for the necessity of de-energizing the circuits as the primary step. Using non-insulated tools can create additional risks when working with live circuits, while improvising makeshift grounding can introduce safety hazards rather than mitigating them. Therefore, the emphasis on de-energizing circuits establishes a baseline for safe practices in electrical system work.