What is the voltage threshold above which only qualified persons are permitted to perform testing and troubleshooting?

The voltage threshold above which only qualified persons are permitted to perform testing and troubleshooting is set at 50 volts. This standard is in place because at voltages above this level, there is a significantly increased risk of electric shock and arc flash hazards. Qualified persons, who have the necessary training and experience, are equipped to recognize these hazards and take appropriate safety measures.

In practice, maintaining safety protocols around electrical work becomes increasingly critical when dealing with higher voltages. As a result, the distinction at 50 volts ensures that only those with specialized knowledge handle work that carries a greater potential for risk, thereby preventing accidents and injuries in the workplace. This also aligns with the overarching goals of NFPA 70E, which emphasizes the importance of electrical safety and the responsible management of electrical hazards.