When should I use arc rated earplugs?
The NFPA 70E Standard requires workers wear hearing protection any time an arc flash incident is likely to occur. This requirement is the same for either arc flash PPE selection method; incident energy analysis or arc flash PPE categories. The Standard states hearing protection required and points to ear canal inserts. Other types of hearing protection are permitted to be used in lieu of or in addition to ear canal inserts provided they are worn under an arc-rated arc flash suit hood.
Oberon conducted Acoustical testing on its products in February of 2004. The results indicate that an arc-rated hood can significantly attenuate the sound hazard, but since the sound level for an arc flash event is so high, the worker using an arc-rated hood still needs to use hearing protection. The arc-rated hood, tested under ASTM 2178, would not allow enough energy to be transmitted through the hood to ignite or melt ear canal inserts or earmuff type hearing protective devices.