Hoods & Face Shields
The 2015 NFPA 70E Standard states in 130.7(C)(10)(b)(2) that an arc-rated hood shall be used when the anticipated incident energy exposure exceeds 12 cal/cm². Face shields must have an arc rating, and be suitable for the arc flash exposure. So the proper arc rated face-shield can be used when exposures are 12 cal/cm² or less. When a face-shield is utilized a properly rated balaclava is required when the exposure is between 4.01 cal/cm² and 12 cal/cm².
A properly rated balaclava is also required when exposures are between 1.2 cal/cm² and 4 cal/cm² when the back of the head is within the arc flash boundary. Eye protection (safety glasses or goggles) shall always be worn under face-shields or hoods. Caution must be used when using an arc rated shield as the tint can reduce visual acuity and color perception. Additional illumination of the task may be necessary.