These tables Hazard Risk Category, PPE requirements, and Flash Protection Boundaries based on arc flash incident energy levels. Reference the 2015 NFPA 70E¢ç: Standard for Electrical Safety in the Workplace¢ç for a more complete reference for Arc Flash Hazard calculations and safety.

Hazard Risk Categories

Source: NFPA 70E, National Electrical Code
Hazard Risk Category Typical Protective Equipment Incident Energy (Cal/cm^2)
0 Nonmelting, non-flammable material 1.2
1 Fire resistant (FR) pant and shirt, or FR coverall 4
2 Cotton underwear plus FR shirt and FR pants 8
3 Cotton underwear plus FR shirt, FR pants with FR coveralls 25
4 Cotton underwear plus FR shirt, FR pants, and multi-layered flash suit 40

General Flash Protection Boundaries

Source: NFPA 70E, National Electrical Code
Arc Location System Voltage Flash Protection Boundary (feet)
Arc in Air 200 - 1,000 Volts 4
Arc in Enclosure 200 - 1,000 Volts 10
Arc in Enclosure Over 1,000 Volts 20

To calculate arc flash incident energy levels and Flash Protection Boundaries for your system, visit Arc Flash Calculator.


Visit the Terms of Use and Privacy Policy for this site. Your feedback is greatly appreciated. Let us know how we can improve.