Canadian Occupational Safety

18 www.cos-mag.com Canadian Occupational Safety n March 2000, Richard Burgess, an industrial maintenance electrician, was doing routine electrical work when an arc flash occurred. A large section of ground wire disintegrated, causing copper to splatter onto his body. A part of the ground wire then whipped towards him and, as he has described the incident, it "branded" him from his wrist to elbow. Burgess suffered severe burns to his hands and face. Six to eight hundred people encounter work- place electrical incidents annually, according to the Association of Workers' Compensation Boards of Canada. In Ontario at least one person in the electrical trade is killed in an electrical incident every year. Yet, for employers, the technical nature of electrical safety can make compliance with safety standards both difficult and costly. The recently revised versions of two key electri- cal safety standards — the CSA's Z462-2018 and the IEEE 1584, published by the Institute for Elec- trical and Electronic Engineers — have introduced huge changes to the industry. Everyone responsible for worker safety must understand these changes and how they affect compliance requirements. In addition to facial and skin thermal burns, electrical hazards can cause lung damage, blind- ness, cardiac arrhythmias, respiratory arrest and death. Electrical hazards exist in all workplaces, although arc flash (an electrical explosion that emits intense heat and light) is most common in heavy industries: manufacturing, pulp and paper facilities, oil and gas and mining, as well as in many renewable industries, such as wind farming. There are three categories of electrical hazards: shock, arc flash and arc blast (a high-pressure sound wave). Of these, safety managers most often focus on shock and arc flash. Arc flashes have different sever- ity levels, based on the amount of heat they release. To understand the arc flash hazards of a work- place, an electrical engineer assesses each hazardous point on a piece of equipment and deter- mines the degree of heat that would be released if an arc flash occurred. The severity level of any point on a piece of equipment is expressed in calories per centimetre squared (cal/cm 2 ). The engineer then puts labels at the hazard points to notify any electrician work- ing there what the hazard level is. The label affixed to any particular arc flash hazard also tells an employer what level of personal protective equipment (PPE) workers should be wearing around that hazard. "Each garment is tested for the maximum amount of incident energy it can protect someone from," says Randy Hillmer, Calgary-based national sales manager at Lakeland Industries. "That amount is expressed as a number, the ATPV (arc thermal pro- tective value), which the manufacturer must attach to the garment. So, if a piece of equipment has an incident energy of 12, then the employer has to pro- vide PPE with an ATPV of at least 12." CSA Z462 The safety manager of any organization that employs people who work near electrical equipment must follow CSA Z462, Workplace Electrical Safety. This standard requires the safety professional to deter- mine what electrical hazards are present in the workplace. Every workplace will have shock hazards, but not every workplace will have arc flash hazards. A major revision in Z462-2018 that concerns shock hazard is a change from a 50-volt to a 30-volt threshold, says Jim Pollard, owner of Stoney Creek, Ont.-based Unlimited PPE. The threshold is the minimum point when an employer is required to complete a shock risk assessment. This change in the voltage definition brings the CSA Z462 into align- ment with the Canadian Electrical Code. In a significant change, the Z462-2018 clarifies and expands on the requirements for risk assessment procedures for both shock and arc flash hazards. This topic, covered in the 2015 standard in a single clause, is now discussed over five clauses to draw attention to and provide more detail about the information required from the employee regarding their risk assessments, says Pollard. One of these new sub-clauses is on human error. In the risk assessment for any specific work task, there is now a requirement for the employer to consider Two recently revised standards are changing the way employers manage electrical safety By Linda Johnson

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