Purpose:
The purpose of this bulletin is to inform T&D and Contractor personnel of important updates to the Arc Rated Personal Protective Equipment (AR PPE) requirements as listed in the Substation Arc Flash Manual (SAFM), Transmission Arc Flash Manual (TAFM), and the Distribution Arc Flash Manual (DAFM) (collectively, AGFMs). This superseding bulletin is meant to clarify OB-0123, date 2/17/2023.
Background:
The AFMs and associated appendices are live documents that may change with or without notice, depending upon system changes and engineering innovations. It is vital to always refer to the appropriate AFM and appendix before any work commencement. Effective immediately, the minimum calorie requirement is being raised to 25 cal/cm system-wide, where Table 3: Arc Flash Hazardous Work Activities, in the applicate AFMs denotes work is an Arc Flash Hazard.
Discussion:
The DAFM Appendices have been revised, and the “Required PPE” has been updated to 25 cal/cm or higher on many AFM appendices. The cal/cm listed is to be adhered to when within an arc flash boundary (AFB). Additionally, when working on live front equipment, the 25 cal/cm minimum requirement will apply.
As a reminder, not all circuits are currently listed in the manual. A process to obtain calculations prior to work commencement has been determined. When calculations are required, send an email to arc.flash@sce.com at least five (5) working days prior to work commencement to request the calorie count.
It is also important to remember how arc flash personal protection equipment (AR PPE) is to be layered to obtain the 25 cal/cm of protection listed in the AFM appendices.
All Hampton Tedder employees must wear Hampton Tedder issued FR arc rated clothing.
Arc rated gloves to be used at 25 cal if not using voltage rated gloves:
