An electrical shock hazard exists when there is a possibility of injury or damage to health associated with current through the body caused by contact or close approach to energized electrical conductors or circuit parts.

Throughout NFPA 70E, safety measures and precautions are generally required when the voltage level for the exposed energized conductor or circuit part equals 50 volts or more. Anything less than 50 volts is not generally considered a dangerous voltage for applying NFPA 70E.

The following definitions can be found in Article 100 of NFPA 70E:

Below is a sample of NFPA 70E. For the complete section, see the actual NFPA 70E text at NFPA.ORG. Once there, click on the free access link to NFPA 70E.

Hazard, Electric Shock (Electric Shock Hazard). A source of possible injury or damage to health associated with current through the body caused by contact or approach to exposed energized electrical conductors or circuit parts.

Informational Note: Injury and damage to health resulting from electric shock is dependent on the magnitude of the electrical current, the power source frequency (e.g., 60 Hz, 50 Hz, dc), and the path and time duration of current through the body. The physiological reaction ranges from perception, muscular contractions, inability to let go, ventricular fibrillation, tissue burns, and death.

Step Potential. A ground potential gradient difference that can cause current flow from foot to foot through the body.

Touch Potential. A ground potential gradient difference that can cause current flow from hand to hand, hand to foot, or another path, other than foot to foot, through the body.