Q&A: Preventing Arc Flash and Shock Hazards

A safety expert sits down with OH&S magazine to discuss why implementing proper risk assessment goes hand-in-glove with having the right PPE.

• By David Kopf
• Jun 01, 2023

Arc flash and shock hazards continue to take their toll. According to the National Fire Protection Association (NFPA), five to 10 arc flash incidents occur every day, and more than 2,000 people are treated annually in burn centers with arc flash injuries.

One electrical safety expert who regularly addresses this subject is Zarheer Jooma, P.E., IEEE (SM’17), an electrical engineer with e-Hazard (e-hazard.com), which provides arc flash and electrical safety training, shares insights into adequate risk assessment, the kinds of necessary PPE, common human errors that often lead to arch flash incidents, and key elements that go into effective electrical safety training programs. Jooma recently sat down with Occupational Health & Safety magazine to discuss why companies need to ensure they are implementing the proper risk assessment, as well as the right PPE. 

OH&S magazine: What goes into adequate risk assessment when it comes to judging the possibility of an arc flash incident?

Jooma: That’s a great place to start off this discussion. One of the governing standards, which is the 2023 version of NFPA 70E, actually breaks risk assessment up into three steps. They are, firstly, identifying the hazards; then, moving on to the proper risk assessment; and then finally coming up with risk mitigation strategies. You know, we always talk about an arc flash risk assessment, but in reality, what we are chasing here is the electrical safety risk assessment.

So, when we talk about electrical safety, we think about the electrical hazards, and there are only two of them: There’s electrical arc flash and there’s electrical shock. And then people ask me, oh, what about the blast on the arc flash? Well, arc flash itself is broken up into two areas: One is the thermal component of it, and the other is a pressure component of it. But without getting into too much detail, the first thing that I would say is you have to do a site visit or a site assessment. You cannot just do an office-based assessment of what’s going on. … In all of my learnings, I always see that the people who are injured the most are the people who do a mental risk assessment.

OH&S magazine: Really? Why is that?

Jooma: Firstly, let me just say I don’t have a problem with somebody just thinking out all of the risks onsite while they are there. But the problem with human beings is that we tend to overestimate our ability. You don’t really know what you don’t know. I’m not going to lean towards either one of these because to me, the correct thing to do is to first go out to site and identify the equipment that you are going to be working on. You need to ask, what am I working on? What are the non-electrical hazards that I’m exposed to? What is my core focus? And while focusing on that, is there not something else that’s going to hurt me? 

That assessment has to start with asking, am I exposed to shock or am I exposed to an arc flash hazard? And very simply, whenever you have energized exposed conductors, generally you are exposed to both a shock and an arc flash hazard. That’d the simplest definition that I can offer. 

Secondly, with regards to arc flash exposure is that an arc flash hazard is present whenever you are interacting with the equipment, and there is an energized path. You might not have any exposed energized conductors—anything within an arm’s reach that you can come into contact with unintentionally. Say, somewhere that I can accidentally get a tool or my finger or any part of my body onto something that’s carrying current that is not insulated. So think about copper bus bars. Think about a termination. Think about the wires that are going into a receptacle, for example. If you can touch that copper, if you can touch that aluminum, if you can touch that brass, then you are exposed to a shock hazard. 

OH&S magazine: And how considerable is the risk?

Jooma: If the energy is substantial enough, then the arc flash hazard could also be detrimental, right? Then the next question you have to ask yourself is: Am I going to be interacting with this piece of equipment? For example, am I going to be turning a breaker on, and am I going to be turning on a switch? And in all of those cases, you don’t have any exposed conductors, but you do have the arc flash hazard that could actually cause harm to you. 

The next thing I would do from a risk assessment standpoint, is ask, can I create an electrically safe work condition? Can I use lockout/tagout principles, test and verify the system, and ensure my equipment is functional? Then I would consider if I have to work on this while the power is still on, such as when turning something off or on, or performing diagnostic work. 

All of these tasks are considered energized work and operations. In such cases, what personal protective equipment can I use? Can I increase the distance between myself and the equipment? Can I utilize remote operating tools? These measures would transition from quantifying the risk to attempting to mitigate it. So, if this hazard has the potential to harm me, what strategies can I employ to reduce the risk? That would be my approach.

OH&S magazine: And, talking about mitigation, obviously one of those items is personal protective equipment. What kind of PPE is necessary to adequately reduce exposure to injury?

Jooma: First, let me go back to the questions of is it shock? Is it arc flash? From our accident investigations, we have observed that in numerous instances, if the worker had protected themselves against electrical shock and adhered to these electrical shock principles, they could have prevented the occurrence of arc flash. This question is one I particularly appreciate because many of us view PPE as a “bulletproof vest” worn when entering a “war zone,” but that’s an incorrect approach. The approach I suggest is to avoid the war zone altogether, right? The governing standards we follow explicitly state that PPE serves as your final line of defense, and safety professionals fully grasp this concept. However, I sense a disconnect between these professionals and users in the field.

I’m referring to the workers who are hands-on with the equipment because we train a significant number of individuals, and I’m fortunate to have personal contact and candid discussions with many of them. They express their thoughts openly, often believing that having the right PPE guarantees safety. However, the correct approach is actually to first attempt to eliminate the hazard through engineering controls, reducing it to a safe level. Of course, if substitution is feasible, it should be considered before resorting to engineering controls. Additionally, we have administrative controls in place, such as training and auditing, ensuring the integrity of systems, all before relying on PPE as the final line of defense. 

Now, to address your question, the single piece of PPE that I would recommend to every individual, whether they are switching equipment or performing electrical diagnostics, is an electrical glove with a suitable over protector. I emphasize this point: nothing surpasses the effectiveness of this combination. In fact, when examining all the fatalities we have investigated in the past 10 to 15 years, I can confidently say that if there had been one piece of PPE capable of transforming those fatalities into survivable incidents, it would have been a properly tested, inspected, well-maintained, and correctly utilized electrical glove equipped with an over protector. 

OH&S magazine: Have there been any recent developments when it comes to gloves?

Jooma: Over the years, these gloves have also undergone advancements. Previously, we utilized rubber gloves accompanied by leather over protectors, using them for both shock and arc flash protection.

Believe it or not, the combination of rubber gloves with leather over protectors does provide a reasonable level of arc flash protection. However, over the years, there has been a growing demand for increased finger dexterity and protection against multiple hazards. For instance, there are situations where clean conditions make the use of leather inappropriate, but there may also be instances involving tasks like wire crimping or cable termination that expose workers to cut hazards. 

That’s where the ASTM F3258 standard comes into play. It is a relatively recent standard that allows testing of hand protection for multi-hazard exposures. Thanks to this standard, we can now assess gloves for their arc flash protection capabilities in addition to other features. It’s quite remarkable that nowadays you can find gloves that offer cut resistance, enhanced grip, and arc flash protection without relying on rubber for electrical shock protection.

OH&S magazine: What about other gear? Are there important trends to stay on top of?

Jooma: There are two significant observations in the industry that we must address. Firstly, companies have now shifted away from using poly-cotton daily work uniforms. These types of clothing not only burn when exposed to an arc flash, but they also melt and adhere to the body, leading to severe and potentially life-threatening burns. However, it’s important to note that most of the fatalities and disabling injuries we have witnessed were not solely caused by the arc flash itself, but rather by the ignition of non-rated clothing due to the arc flash. Based on this knowledge and the awareness we have been striving to raise over the past decade or more, it is crucial to transition your workers’ daily workwear uniforms to arc-rated clothing. This means ensuring that the shirts and pants provided to workers have some form of arc rating to mitigate the risks associated with arc flash incidents.

Now, everyone has been fantastic. Over half of the major industry players have introduced dual arc-rated clothing, which not only shields against flash fires and gas fires but also provides protection in the event of an arc flash. However, where is the gap in this PPE? The issue lies in the misconception that wearing an arc-rated long-sleeve shirt and arc-rated pants is sufficient. Where do we commonly witness arc flash incidents? They tend to occur on individuals’ hands, neck, and face. The question is: why? It’s because people fail to complete the arc flash protective personal protective equipment as intended. It is imperative to cover your hands with either an arc-rated glove or an electrical glove accompanied by a heavy-duty leather over protector to ensure proper protection.

Your face must be adequately protected with safety eyeglasses and hearing protection. Additionally, you need to wear a balaclava, which is similar to a pullover or ski mask, as an extra layer of coverage. Furthermore, it is essential to wear a hard hat with a face shield on top. However, if this combination feels too burdensome, there is an alternative. You can still wear the necessary safety glasses and hearing protection, but instead of the separate balaclava and face shield, you can opt for a one-piece flash suit hood that covers your entire head. This completes the required PPE ensemble. It is worth noting that PPE should always be regarded as your final line of defense.  

This article originally appeared in the June 1, 2023 issue of Occupational Health & Safety.