Before working on a transformer, which standard must be followed according to safe work practices?

The correct choice emphasizes the importance of following NFPA 70E standards, which specifically focus on electrical safety in the workplace, particularly when working on or near energized electrical equipment such as transformers.

NFPA 70E provides guidelines for determining the level of shock and arc flash hazards present and outlines appropriate personal protective equipment (PPE) and safe work practices that must be implemented to protect workers from electrical hazards. For anyone who might be working on transformers, adhering to these standards ensures proper risk assessments are conducted and necessary precautions are taken to mitigate the risk of electrical shock and related injuries.

Understanding and following NFPA 70E is crucial because it not only covers the safe operation and maintenance of electrical equipment but also promotes a culture of safety among electrical workers. This dedication to safety helps prevent accidents that can occur during maintenance work on transformers, which can involve high voltage and other hazardous conditions.