The new 2015 NFPA 70E, Annex H, recommends wearing a faceshield for projectile protection at 1.2cal/cm2 arc flash hazard or less. What data is that requirement based on? Is there a study out there that shows projectiles are likely from such a low arc flash hazard, or are there documented incidences of people having been injured by projectiles at low arc energies? Or did someone just decide that this rule was a good idea?
I'm looking for any kind of supporting evidence I can use to demonstrate that this extra PPE is necessary. Because the annexes are "informational," this PPE is not a requirement of NFPA 70E, but I want to settle our internal discussion of why it's a good idea.