Arc Flash and Shock Hazards CSA Z462 Workplace Electrical Safety Standard — Management of Change

Terry Becker

Sept 17, 2020

By Terry Becker

We are quickly approaching January 2021 and publication of the 5th edition of the CSA Z462 Workplace electrical safety Standard. This is good news for Canada as we continue to evolve in our identification and management of the electrical hazards of arc flash and shock. But as I have quoted in the past, we need to ensure we are getting it right, and there is still a lot of work to be done. Most of the focus has been on arc flash and I am concerned that the electric shock hazard has been neglected.

Managing change is critical to any business. The application of the CSA Z462 Workplace electrical safety Standard has changed, is changing and will continue to change how energized electrical work tasks are implemented. De-energizing electrical equipment before any repair or alteration is now a priority, a mandatory requirement unless there is validate justification and an energized electrical work permit (EEWP) is executed. Implementing an energized electrical work permit policy and workflow process ensures that certain work tasks do not proceed unless formally strictly authorized as documented in an employer’s electrical safety program. In addition, a formal documented risk assessment procedure would also be required to be completed for the work task and included in the electrical safety program’s requirements.

Since it was first published and available in January 2009, the CSA Z462 Workplace electrical safety Standard has made a significant impact on mitigating exposure and/or reducing the risk related to performing energized electrical maintenance work tasks. The additional benefit when CSA Z462 is applied correctly is placing focus on the electric shock hazard for all workers who use portable cord-and-plug-connected electrical equipment and extension cords and need to understand when then need a GFCI and to pre-use test it. CSA Z462’s correct application through the use of a compliant electrical safety program will continue to benefit industry and worker safety.

That said there continues to be misunderstanding, misinformation and conservative interpretation of the information presented that is related to the understanding of arc flash and shock hazards, when workers are actually exposed, and what the employer and the worker need to do. Training received continues to focus on “arc flash awareness” or “arc flash training,” neglecting shock in the title and the content of the training. Training provided has used fear-based tactics and the instructor may not have been able to substantiate correctly the content in the CSA Z462 Standard. The training provided did not include content on the overall risk assessment procedure and the application of the hierarchy of risk control methods. With respect to arc flash the students may have wrongly been informed when an arcing fault is actually likely to occur. Conservative assessment and fear trends to qualified electrical workers refusing to complete energized electrical work tasks.

An arc flash incident energy calculation greater than 40 cal/cm2 continues to be communicated as “Dangerous” and “No PPE Available” in engineering arc flash hazard incident energy analysis studies and issued reports. The new IEEE 1584 Guide for Performing Arc-Flash Hazard Calculations was published in its 2nd edition with new formulas, and new parameter selections that if conservatively selected can result in a 200% increase in previously calculated incident energy levels using the 2002 formulas. Engineering reports that are incomplete and include misinformation continue to be issued to the client. We still need to clarify that arc flash PPE is specified with an arc thermal performance value (ATPV) and not an HRC#, CAT# or arc flash PPE category # when incident energy has been calculated. To rectify this, the CSA Z462 Standard 2018 Edition did include Table 3 Selection of arc-rated clothing and other PPE when the incident energy analysis method is used. With respect to management of change, employers need to decide when they will update existing arc flash hazard incident energy analysis studies using the new IEEE 1584 formulas and parameters. When employers do decide it is recommended that they define a strict technical specification and that the employer understands and controls the parameter selections used. When updating installed arc flash and shock equipment labels, employers should ensure the equipment label is also simple and compliant, with specific focus on ensuring the footer clearly identifies the electrical equipment ID and the electrical protective device ID.

Figure 1 — Simple & Compliant Arc Flash & Shock Equipment Label
Arc Flash and Shock Hazard

 

 

 

 

 

 

 

 

 

 

Change is positive if it is managed properly. With respect to electrical safety, a short- and long-term plan should be developed, a schedule determined, and appropriate staff (e.g. management, supervision, HSE, qualified electrical workers, task qualified workers, qualified operations workers, and non-electrical workers) or contractors engaged. Any new requirements in the CSA Z462 Standard should be reviewed, substantiation for interpretation provided against established policies, and practices and procedural requirements defined in the employer’s electrical safety program. A formal structured process should be followed.

As we move to the 5th edition of the CSA Z462 Standard, it is an opportunity for you and your company to step back from what you have done to date with respect to arc flash and shock, and audit it or complete a gap analysis. Using a structured approach your electrical safety program should have an internal electrical safety audit process. Measure your company’s performance to date, identify deficiencies in your policies, practices and procedural requirements and if you have applied the hierarchy or risk control methods correctly. Seek out continuous improvement opportunities, and correct errors that may have occurred in the past.

A continuous improvement process should be adopted. The employer should ensure that the documented and implemented policies, practices and procedural requirements are current to the latest edition of the CSA Z462 Workplace electrical safety Standard, as the 2021 edition will bring with it additional changes and updates from the 2018 edition. You need to update your electrical safety program, train your staff and contractors on the updated requirements of your electrical safety program and ensure you due diligence to OH&S regulation is current, valid, documented and defendable if you ever have an electrical incident.

If you are interested in discussing the pending changes to the CSA Z462 Standard, 2021 Edition or have any questions or comments you may have regarding this article, please contact Terry Becker, P.Eng., CESCP, IEEE Senior Member; 1-587-433-3777;terry.becker@twbesc.ca; www.twbesc.ca.

Terry Becker, P.Eng., CESCP, IEEE Senior Member is the first past Vice-Chair of the CSA Z462 Workplace electrical safety Standard Technical Committee and currently a voting member and working group leader for Clause 4.1 and the Annexes. Terry is also a voting member on the CSA Z463 Maintenance of electrical systems Standard and a voting member of the IEEE 1584 Guide for Performing Arc-Flash Hazard Calculations. Terry has presented at conferences and workshops on electrical safety in Canada, the USA, India, and Australia. Terry is a Professional Engineer in AB, BC, SK, MN and ON. Terry is an Electrical Safety Specialist, Management Consultant at TW Becker Electrical Safety Consulting Inc. and can be reached at 1-587-433-3777 or by email: terry.becker@twbesc.ca.

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