Jim Phillips describes his method for simplifying arc flash labeling and possibly eliminate the need to re-label when there are system changes. Use a standardized arc flash boundary and the arc rating of the PPE.  If/when the incident energy and/or arc flash boundary changes, as long as the new values do not exceed the standardized values on the label, there is no need to re-label.  Just add a “maintenance sticker” to re-validate the label for the next review cycle.