According the National Electrical Code/National Fire Protection Agency, the term “electrically safe work condition” was first introduced into the electrical code in 1995. Deenergizing (locking and tagging out of service) any equipment or electrical systems is a fundamental requirement prior to working on equipment or circuits. In safety, we call it LOTO or lockout/tagout. Working on live or potentially live equipment requires greater level of precaution and special flame resistant protective equipment and clothing (down to the underwear).
For more information, contact CHESS or refer to this recent article.