The NFPA 70E-2015 was “issued by the Standards Council on July 14,2014 with an effective date of July 29, 2014, and supersedes all previous editions�.[/i]

Can NFPA 70E-2012 still be used ?
ie.
Can the IEEE 1584-2002 analysis method still be used select the PPE based on the incident energy at the corresponding working distance, and the NFPA 70E-2012 PPE Table 130.7( C)(16) ?

Can the arc flash label have both incident energy at the corresponding working distance and the required PPE Level ?

According to what I read in NFPA 70E 2015 both PPE and Incident Energy CANNOT be a part of the label. It's an EITHER/OR situation. I think more to the question is - How soon do companies that have already posted older requirements have to convert to "2015"?

Since 70E is a voluntary standard, there's no real way to enforce specific editions. But it would look pretty ridiculous from a legal standpoint to stick to say the 1976 edition of NEC for instance. Which may seem laughable but a certain federal agency still clings to that particular edition.

Even under 70E-2012 though, H/RC ratings and incident energy NEVER mixed. 2015 edition just makes this more clear. If you use the task tables, you use the associated PPE table. If you use a calculated incident energy, you use the table in Annex H, or manufacturer's recommendations based on say ASTM 1959. The issue, and this is nitpicking, is that "H/RC" incorporates both a hazard assessment and a risk assessment in a combined rating. Using the cal/cm^2 ratings in the table is reading it "backwards" whereas the table is "forwards" in Annex H. Either way an "H/RC 2" is not "8 cal/cm^2". In fact for switching activities on medium voltage equipment, the incident energy can be much higher than this for example but under the logic of 70E-2012, it is reduced to H/RC 2 and only 8 cal/cm^2 PPE is required, so clearly H/RC 2 is NOT the same as <= 8 cal/cm^2.

My company is good with using 70E-2015 going forward for label content of newly applied labels. For the labels already on equipment (a few thousand) we do not plan to change them out. In our case, our labels are based on a calculated incident energy (cal/cm2) and we included the HRC at the time as means to simplify PPE selection. I believe the key is, do the labels provide the information to allow the employee or electrical contractor, to select the proper arc rated clothing and PPE for the arc flash hazard of that equipment.

Include the incident energy, come up with some sort of company method to identify PPE level (i.e. not HRC) and you are fine.