Seeking Arc Flash PPE

You're not looking for arc flash PPE. If you were, you would have simply Googled it.

arc flash personal protective equipment (PPE). The materials are tested for their arc rating. The arc rating is the maximum incident energy resistance demonstrated by a material prior to breakopen or at the onset of a second-degree skin burn^. Arc rating is normally expressed in cal/cm² (or small calories of heat energy per square centimeter). The tests for determining arc rating is defined in ASTM F1506 Standard Performance Specification for Flame Resistant Textile Materials for Wearing Apparel for Use by Electrical Workers Exposed to Momentary Electric Arc and Related Thermal Hazards.

Selection of appropriate PPE, given a certain task to be performed, is normally handled in one of two possible ways. The first method is to consult a hazard category classification table, like that found in NFPA 70E. Table 130.7(C)(9)(a) lists a number of typical electrical tasks are various voltage levels and recommends the category of PPE that should be worn. For example when working on 600 V switchgear and performing a removal of bolted covers to expose bare, energized parts, the table recommends Category 3 Protective Clothing System. This Category 3 system corresponds to an ensemble of PPE that together offers protection up to 25 cal/cm² (105 J/cm² or 1.05 MJ/m²). The minimum rating of PPE necessary for any category is the maximum available energy for that category. For example, a Category 3 arc-flash hazard requires PPE rated for no less than 25 cal/cm² (1.05 MJ/m²).

The second method of selecting PPE is to perform an arc flash hazard calculation to determine the available incident arc energy. IEEE 1584 provides a guide to perform these calculations given that the bolted fault current, duration of faults, and other general equipment information is known. Once the incident energy is calculated the appropriate ensemble of PPE that offers protection greater than the energy available can be selected.

PPE provides protection after an arc flash incident has occurred and should be viewed as the last line of protection. Reducing the frequency and severity of incidents should be the first option and this can be achieved through a complete arc flash hazard assessment and through the application of technology such as high resistance grounding which has been proven to reduce the frequency and severity of incidents.

After seeing the aftermath of a 11KV flash over, I'd be dubious as to what protection PPE would afford.

The case I relate to the substation was unattended so no injuries. I had to chisel bits of the OCB's porcelain connection spouts out of the brick wall, I don't think a full suit of armour would have saved anyone!

You may like to also visit http://www.arcflashforum.com/ where there is much discussion as to the merits of PPE, and alternative ways of reducing risk/injury from HV switching.