In 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 workplace 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 electrical safety standards — the CSA’s Z462-2018 and the IEEE 1584, published by the Institute for Electrical 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, blindness, 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 severity levels, based on the amount of heat they release.
To understand the arc flash hazards of a workplace, an electrical engineer assesses each hazardous point on a piece of equipment and determines 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/cm2). The engineer then puts labels at the hazard points to notify any electrician working 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 protective 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 provide PPE with an ATPV of at least 12.”
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 determine 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 alignment 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 the role of human error and its potential negative effect on people, processes and work environment. There is also a new section on human performance and electrical safety.
“Much of the buzz in the electrical safety industry for the past five years has been around human error, human performance and behaviour. The human element is a significant concern. We have all these controls we can put in place, but the one factor that is most difficult to overcome is the human element,” Pollard says. “It can be as simple as not wearing the right arc flash PPE or wearing too much PPE and not being able to perform the work task properly.”
The revised Z462 standard also removes the upper limit for work. In the electrical industry, it has long been accepted that work cannot be performed above the severity level of 40 cal/cm2, but this is not true, Pollard says. Workers wearing proper PPE can safely perform tasks above 40 calories, he explains.
“We deleted this (limit) in the 2018 standard to help dispel that myth and help educate industry that you are permitted to use protection above 40 calories,” he says. “There is no limit. There are arc flash suits that exist up to 140 calories.”
The revised standard includes additional requirements for documentation; for instance, job safety planning must now be documented. There is also a clause on “establishing an electrically safe work condition,” which contains information related to the control of hazardous energy, lockout and other methods that are applied specifically to electrical equipment.
Moreover, as of 2018, suppliers and manufacturers are required to demonstrate their level of conformity to all applicable standards.
“Now it’s in the Z462 standard that you can require your supplier or manufacturer to provide a declaration of conformity. That’s a legal document, a legal way for you to hold the manufacturer accountable,” Pollard says.
In November 2018, a new IEEE 1548, used by electrical engineers to calculate arc flash levels, was released.
The revised standard was based on almost 2,000 tests and introduced a new way to calculate the incident energy level of electrical equipment. These tests showed that all calculations done in the past were unreliable. The problem arises from the fact that different pieces of electrical equipment are designed with different electrode configurations: some are vertical and some are horizontal. The incident energy calculation contained in the previous version of the standard had really only accounted for vertical electrodes.
With horizontal electrode configurations, the new tests produced incident energy levels that were up to 330 per cent higher than the levels produced from calculations conducted according to the original IEEE 1584.
The new standard means employers should go back and have all their electrical equipment re-calculated, says Jon Travis, CEO and co-founder of Saint John, N.B.-based Leaf Electrical Safety. This task will be costly, but important because there could be a label on a piece of equipment that says 5 cal/cm2 when really it’s 20 cal/cm2, which is a great deal more heat energy.
“An electrician would go up to a label and say, ‘It’s 5 cal/cm2. I’ll get my protective clothing that is rated 8 cal/cm2, so I know I’m good.’ But it’s really 20, and the clothing they have on is not good enough,” says Travis. “Most people have a shirt and pants that are rated 8 or so. They would also have a set of clothing rated 40. They should be wearing that 40-calorie suit more often, but they don’t know that because the calculations were done prior to the release of this new 1584.”
However, though the previous incident energy calculation needed to be revised, it is important to keep in mind that the new IEEE 1584 does not mean all incident energy assessments done in the past are incorrect; rather, it indicates only those calculations done on equipment with horizontal configurations are wrong. From the perspective of increased hazard potential, the good news is that the arc flash PPE that most workers are wearing now will continue to provide adequate protection because the actual number of incorrect energy levels in any workplace is likely to be quite low.
“Not all electrical equipment has horizontal electrodes, most have vertical electrodes. So, for the most part, we shouldn’t see a huge change in what the calculated values are for incident energy. But you don’t know until you go back and you re-assess the equipment,” Pollard says.
If there is a possibility of arc flash in a workplace, the safety manager needs to select the correct level of arc flash PPE based on the incident severity level at any particular point where a worker might be working. There are two methods of selecting PPE. The first, called the “incident energy analysis method,” requires an analysis of electrical equipment done by an electrical engineer. The second, used by most employers, is based on tables. The person consults the arc flash PPE category tables, included in the CSA Z462, to determine what level of PPE protection a worker needs.
While the “category method” is a more cost-effective way to select PPE than is the incident energy analysis method, it is less accurate. Generally, the category method tends to lead to over-protection of workers, says Hillmer.
“It’s a reasonably simple way to select PPE. With the category method, there’s a range that each garment falls into. So, you know the approximate incident energy of a particular task, and you look for the corresponding PPE range. You have to wear at least that category of clothing. So, you may not need as much protection, given the incident energy, as you are choosing,” he says. “Whereas if you use the incident energy method, which means you know exactly what the incident energy of that particular task is, then you can choose your clothing based on the actual hazard.”
While the revision of the incident energy calculation in the latest IEEE 1584 means all calculations should be re-done, it is unlikely most employers will be able to do this all at once. The task is too big and costly. They must continue, therefore, choosing PPE according to the currently available category tables, though these tables were created prior to the introduction of the new calculation, Pollard says.
“We’re going to go as status quo for now until industry has time to catch up. It will take a long time.”
Still, employers should be planning now to review all their incident energy hazards sometime in the future. They should not be using the table method five years from now.
“You might want to document a plan stating you’re going to use the table method now because that’s all you have, but next year you will start doing calculations on equipment that you understand may have a horizontal electrode configuration,” Pollard says. “Or, you might say, ‘Let’s just take a couple of pieces of equipment that we do the most work on, and let’s do the calculation to see if it’s any different than what we’re currently wearing for protection.’”
One of the consequences of the new IEEE standard, Pollard believes, will be that many employers will deliberately over-protect workers. He knows of some companies that have already reacted to the IEEE change by adding a certain percentage to the value of their past calculations. They will continue to provide too much protection until they have time to adjust their calculations.
“That’s going to lead to additional arc flash PPE for the worker, which if not selected appropriately, could lead to human error and contribute to the likelihood of an arc flash incident because arc flashes for the most part are caused by human error,” Pollard says.
Travis says he does not think the new standards will have a very great impact. While he agrees employers should re-do all their incident energy calculations, his big concern is the number of employers who are not compliant with either the Z462 or the IEEE 1584 now. Most of them have never tried to analyze their equipment to see what the hazard level is.
“It’s not very often that I come across a company that not only knows what their hazard level is but also has the right PPE in place, has the right procedures in place and their workers are knowledgeable. There are three or four pillars of this thing,” Travis says.
However, the revised Z462 is more practical than previous versions, which tended to be complicated and very technical, he says. This is a step forward and will likely increase compliance.
“It’s challenging. It’s a lot of work to be compliant with any safety standard. And we can get carried away. I always want to come back and just make it practical for people. With standards, there can be so much information, you could drive yourself crazy trying to comply with it all,” Travis says. “But if you look at the fundamentals and ask what the most important things are that we need to do, you’re going to be in pretty good shape.”
Linda Johnson is a Toronto-based freelance journalist who has been writing for COS for eight years.
This article originally appeared in the June/July 2019 issue of COS.
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