The labeling must be to ANSI Z535 for the simple label that meets the intent of CEC Part 1 Rule 2-306 and a detailed label that would be installed at the discretion of the electrical equipment owner, and it not mandatory to install.
The simple label is required on any new equipment after the 2006 CEC Part 1 was adopted in your Province or Territory, not grandfathered either.
A company must decided what format they want for the detailed Arc Flash & Shock Warning label if they have completed detailed engineering based Arc Flash Hazard Analysis or the Table Method.
If you use the Table Method you can only indicated the HRC of arc rated protective clothing.
If you complete detailed engineering based AFHA your lable should NOT include a reference to HRC, but should indicate that arc rated clothing (either ATPV or EBR) be specified that has an arc rating greather than the incident energy at the assumed working distance indicated on the label.
Technical interruptation of Z462 is that you cannot call arc rated protective clothing by an HRC unless you used the Table Method.
Regards;
Terry Becker, P.Eng., CSA Z462 Technical Committee Voting Member
ESPS Electrical Safety Program Solutions INC.
http://www.esps.ca
terry.becker@espsi.ca