Incident Prevention - Dedicated to Utility & Safety Professionals

The need to safely access hard-to-reach areas continues to be a struggle in numerous industries, including utilities. Historically, people have pushed the limits of machinery and designed better tools in attempts to access such areas. In the early days of automobiles, for instance, enthusiasts modified and improved the designs of their vehicles, enabling them to travel farther across terrain on which the vehicles were never originally designed to travel. As technology and industry continued to progress, manufacturers began to design vehicles specifically intended for off-road applications, which led to the development of a new vehicle category: the all-terrain vehicle (ATV). Over time, the ATV label – which originally applied to Jeeps – became synonymous with four-wheelers, or quads. As even more time passed, ATVs eventually became useful not only as recreational vehicles but as staples of off-road transportation for industrial uses as well.

While ATVs were first produced specifically for utility use in the early 1980s, the utility task vehicle (UTV) – also known as a side-by-side – was initially launched by Kawasaki in 1988 as the MULE, an acronym for multi-use light equipment. The UTV provides features that cater better to industrial applications, such as more seating and cargo capacity. ATV-type vehicles existed long before the 1980s, but they were designed and used almost exclusively by the recreational market. Since utility use of ATVs and UTVs did not exist before the 1980s and became more commonplace in the 1990s, the market and technology are still relatively new from a regulatory standpoint. However, due to significant advancements in the functionality and reliability of these vehicles, industrial use has grown dramatically in recent years. That has prompted an increase in the need to identify proper use of these machines as transportation to access job sites or as tools to aid workers in performing tasks.

Have you ever thought about the similarities between solving a puzzle and transforming a safety culture? For one thing, the challenges of solving a puzzle – no matter if it’s a jigsaw puzzle, a Rubik’s Cube, a riddle or a maze – range from simple to difficult, just as the challenges of a safety culture transformation do. And second, people approach solving puzzles and creating cultural transformations in myriad ways.  

Whether you’re trying to solve a puzzle or transform the way your organization handles safety, two things are for certain: to be successful in your mission, you must have all the necessary pieces before you get started, and you must then fit them into their proper places. In the safety world, those pieces include a clear vision, commitment, a positive attitude, accountability, clear communication and leadership support. As you fit each piece into its appropriate spot, you take one step closer to your goal – a strong safety culture. But a piece placed in the wrong spot, or one that’s missing altogether, can lead you in the wrong direction.

So, how do you begin to transform your organization’s safety culture if it is missing pieces, has interdependencies and can be approached in more than one way?

Sergio is repairing equipment at a power station when he feels a twinge of discomfort in his lower back. Per company policy, he informs his supervisor. What happens next is likely to have a critical impact on the outcome for Sergio and his employer.

Let’s assume the supervisor instructs Sergio to stop working and visit a clinic for evaluation. At the clinic, the treating provider conducts a physical exam, orders some diagnostic tests and writes a prescription for medication to relieve pain and inflammation. Sergio takes the afternoon off and returns to work the next day with restrictions. The encounter is recordable and results in a workers’ compensation claim.

Now, let’s consider an alternative scenario. Sergio and his supervisor call or use a smartphone application to contact an injury management triage center. Sergio describes his symptoms to an occupational health nurse or physician who offers reassurance and care guidance. He is given the option of a clinic visit, but with instructions from the clinician, Sergio instead voluntarily agrees to self-administer first aid.

After applying a cold pack to his back and taking a nonprescription anti-inflammatory medication approved for use at the worksite, Sergio resumes work and is able to safely finish his shift. A claim is not filed and there is no case to record.

In the first scenario, a routine complaint of low-back discomfort diverges onto a path with the potential for high medical costs, productivity loss, delayed recovery and litigation. In the second scenario, Sergio is given choices that include using work – an activity “prescription” – as therapy during recovery. Sergio is empowered to successfully manage his condition without worrying about making it worse or potentially missing work.

For over 100 years, PECO – a Pennsylvania utility and member of the Exelon utility family – has been supplying electricity and natural gas to customers across southeastern Pennsylvania, including those in Philadelphia and its surrounding suburbs. PECO has hundreds of miles of utility poles and thousands of circuit miles of medium-voltage distribution cables installed in conduit and manhole systems.

With all this infrastructure, it is only natural that wear and tear will occur, which can have an impact on the distribution system. Over the decades, PECO has experienced numerous failures of distribution system components, some of which developed into fires that were difficult to combat due to poor weather conditions. Unfortunately, local volunteer fire departments typically are not equipped to deal with these types of fires, and even city fire departments, whose workers receive training on electrical fires, sometimes have a difficult time extinguishing them.

Regulations and Extinguishing Agents
Another issue PECO employees have had to deal with is the type of fire extinguishers available in their work vehicles. For utilities that have service fleets and operate under federal guidelines, the U.S. Department of Transportation requires those fleet vehicles to carry fire extinguishers. Per Federal Motor Carrier Safety Regulation 393.95, “Emergency equipment on all power units,” each extinguisher must have a gauge to indicate if the extinguisher is fully charged and a label that displays its UL rating. Extinguishers also must be securely mounted and readily available and accessible for use at all times. In addition, a vehicle transporting hazardous materials must be equipped with an extinguisher with a UL rating of 10 B:C or more. If the vehicle is not transporting hazardous materials, it must carry one extinguisher with a rating of at least 5 B:C, or two extinguishers, each with a rating of 4 B:C or more.

In the past few months, I have received comments and inquiries from all over the U.S. regarding what appears to be stepped-up enforcement of both load securement and vehicle weight rules. It’s not unusual that these topics garner attention from the U.S. Department of Transportation when it comes to carriers, but this recent uptick seems to be for smaller commercial vehicles, mechanics trucks, pressure diggers, and bucket and digger derrick trucks.

Not all utility safety professionals may be up to date on this topic because DOT issues are not front-burner issues. Typically, the human resources department handles a driver’s qualification file and drug testing for the DOT. Drivers at utilities only spend a few hours a week on the road between calls and jobs, idling most of the workday. We recognize that there are utilities with rigorous DOT management programs for equipment and drivers, but generally we find a more lax daily inspection protocol among utilities and contractors than you would find with a carrier. That might be justified considering the time a utility truck spends in transit compared to a carrier that is preparing to put a rig on the road with two drivers for 20 hours a day over the next two weeks. But it’s not the rule, and mistakes or latitude over trucks can suddenly become a serious liability when one of those overlooked trucks loses a steering link as it is driven through a school zone full of first-graders.

Craft Worker Compliance
Recently there have not been any changes of note in the rules for vehicle weight and load securement; however, it appears that some of the latitude taken by utilities, if not given by the DOT, has caught the attention of those responsible for enforcement of the rules. 

In the last couple of years, state enforcement agencies used local media to inform local commercial businesses – that are not carriers – that they would be stopped if they did not appear to comply with loading and marking standards for their class of vehicles. In Arizona, New Mexico, Washington and Colorado, my colleagues and I began to hear of roadside stops involving lawn maintenance companies and small construction concerns that were pulling dual-axle, 5-ton trailers behind a Ford F-350, carrying loaders, backhoes and super lawn machines. That soon extended to power company trucks, especially those loaded with large wire reels. I even heard of one instance in which state enforcement set up scales in a shopping center parking lot on a well-known route out of a power company service center. Within 40 minutes they cited 22 vehicles for being overweight. You would think drivers would have warned others, but the DOT waved them into the parking area before they started weighing and inspecting the vehicles, so no one knew what to expect. It shouldn’t have been – but it was – a big surprise for that utility’s fleet management to learn what kind of loads lineworkers were putting on those trailers.

It has taken the electric utility industry many years to understand induced voltage. When I started working in the 1960s, it was explained to me that voltage remaining on de-energized lines was static voltage that had to be bled off or else it could be deadly. Now, when I speak to groups about temporary system grounding for the protection of employees, I occasionally still hear the term “static voltage” being used to describe what really is induced voltage from a nearby energized line. Even today, not everyone in the industry completely understands induced voltage.

So, what exactly is induced voltage? Here are some things utility safety and operations professionals should understand. The electromagnetic field around an energized conductor produces capacitive and magnetic coupling to all nearby objects within the electromagnetic field. The voltage level of the energized conductor and the physical length of the de-energized conductor that is exposed to the energized (source) conductor will determine the amount of voltage on the de-energized conductor or equipment. A de-energized conductor or piece of equipment will remain energized as long as the source remains energized and de-energized equipment remains ungrounded. Properly installed temporary system safety grounds can be used to create an equipotential work zone for employees.

The induced voltage found on de-energized equipment is not static, and it can’t be bled off. System safety grounds that have been installed simply give the induced voltage a conductive connection to ground. Once grounds are removed, the induced voltage returns to exactly the same amount of voltage instantly. It is voltage of 60 cycles per second in a steady-state condition, because there is no path in which electricity can flow other than the energized, isolated conductor or equipment. If grounds are applied to de-energized conductors, the voltage immediately will collapse to near zero, but now the physics have changed and a current flow is established in the system safety grounds. The amount of current flow in ground sets is determined by the amount of induced voltage on the de-energized equipment before the grounds were installed, and the resistance of the ground set and the ground. In addition, the more ground sets that are applied to a de-energized line, the less current flow there is in each set of grounds.

Q: Whenever we see graphics for single-point grounding, it’s always a cluster, a connection to the neutral, a connection to a phase and a chain connecting to the other two phases. But when we check with other utilities or consultants, we see all kinds of arrangements, such as bracket grounds with a single point or two sets of single-point grounds bracketing the workspace. Where do we find the definitive arrangement, and why are there so many variations?

A: Under OSHA, the employer is solely responsible for determining how they will meet the requirements of 29 CFR 1910.269(n)(3), “Equipotential zone,” which requires that grounding of de-energized phases be installed in an arrangement that prevents employees from being exposed to differences in electrical potential. In addition to 1910.269(n)(3), there also is Appendix C to 1910.269, “Protection From Hazardous Differences in Electric Potential,” as well as IEEE 1048-2016, “IEEE Guide for Protective Grounding of Power Lines,” a consensus standard that may be considered the authoritative best practice. IEEE 1048 is filled with detailed electrical data – from modeling to application – to explain how to create equipotential protection and effective tripping of grounded circuits that may inadvertently be energized.

What happens to a saltwater fish if we put it in fresh water? No matter what that fish does, no matter how well it can swim, no matter how strong it is and no matter how hard it tries, it cannot survive because we put it in the wrong environment.

When it comes to human performance, HP principle three states that individual behavior is influenced by organizational processes and values. It implies that incident causation goes deeper than individuals, and that to prevent incidents, organizational (systems) deficiencies must be identified and corrected. The challenge for an organization is to create an environment in which employees – the organization’s greatest asset – perform at their highest level. You do not want to create an environment in which latent organizational weaknesses set employees up for failure.

Us vs. Them
Imagine a group called Us and a group called Them. Them has a package labeled Profit that needs to get from Point A to Point B on or before a day called Standard. Them creates directions on how to get from Point A to Point B, which are contained in the Map. Them gives the Map to Us and instructs Us to go to Point A, pick up Profit and deliver it to Point B on or before Standard.

Us arrives at Point B two days late with only part of Profit because Us got lost. Them is furious and blames Us for losing part of Profit by not arriving at Point B on Standard. Us blames Them, complaining that the Map was wrong, which caused Us to get lost and be late. Two weeks later, this scenario is repeated, with more of Us losing part of Them’s Profit, so Them sends Middle Man to investigate and determine corrective action.

The names Nathan Baker, Zackary Randalls, Alex Boschert and William Froelich may not be familiar to you, but their stories are tragically important for utility workers. Nathan worked for East Mississippi Electric Power Association in Clarke County, Mississippi. Zackary was employed by Pacific Gas and Electric Co. (PG&E) in Fresno, California. And Alex and William worked for Laclede Gas Co. (LGC) near St. Louis. Except for Alex and William, who were employed by the same company, there is no evidence that these men knew each other or their paths ever crossed, so what thread binds them together? They were murdered while doing their jobs for their respective companies. In a horrible twist of fate, three of the men were killed within a week of each other in 2017.

In 2012, Nathan was making a routine collection/disconnect call at a residence when he was shot; his body was dumped in one location and his truck abandoned in another. In 2017, Zackary was sitting on the passenger side of a PG&E truck when a gunman walked up to the window and fired at him. A few days later, Alex and William were connecting a residential natural-gas line when a man, believed to be upset about his electricity bill, shot the two men and then turned the gun on himself.

Troubling Reminders
These stories are troubling reminders of a trend of violence aimed at utility workers. Utilities go to great lengths to ensure their employees have the skills and training necessary to safely do their jobs, but there has been less of a focus on utility worker security. This has to change. It is time to rethink utility security. From the front door of the office to the crews in the field, we must change how we go about protecting employees. Lives depend on it.

When you mention “utility” and “security” in the same sentence, many people think of cybersecurity or physical security of large-scale infrastructure sites. Many have heard about the cyberattack on the Ukrainian electricity grid in 2015 and know about the steps taken in the U.S. to secure the grid. Some conceptualize utility security as protection against attacks like the one on the PG&E Metcalf substation – a major transmission grid link – that occurred in 2013. Although these are critically important security issues, they are not the only ones. Safety managers and senior staff with safety and security responsibilities also should focus on improving the security posture of utilities at the local level. This means securing office complexes, warehouses and operational facilities; taking steps to target-harden local transmission and distribution; and improving the protection afforded to both office and field personnel, whether company or contractor.

“Are you calling his family, or do you want me to?” the superintendent asked. The project safety manager replied, “I’ll call his emergency contact after I find out where the ambulance is heading. Can you call the division manager and give her an update?” The superintendent shook his head as he surveyed the scene and said, “I’ll have to keep it short and simple for now, but tomorrow morning we’re going to need to be able to explain to everyone how a 19-year-old kid with three months of experience was able to jump into that piece of equipment and put it into an overhead power line.”

Although this is a fictional conversation, it may hit close to home for numerous industry workers, especially if your company is adapting to rapid growth by hiring new workers, also known as short-service employees (SSEs).

In its August 2017 issue, Incident Prevention published an article I wrote titled “Overcoming the Effects of Rapid Growth” (see https://incident-prevention.com/ip-articles/overcoming-the-effects-of-rapid-growth), which described how leaders can use operational analysis and powerful communication skills to overcome the effects of rapid company growth. In this article, I’m going to expand upon that topic by shifting the focus to overcoming the effects of rapid growth through SSE onboarding, field mentoring and coaching. That’s because if the Crucial Conversations skills I wrote about in the last article made an impact, and you now have hired the additional people you need to accomplish your company’s ever-growing mission, then it’s likely you are facing a different problem: How do I get these new people up to speed so they meet our quality and safety expectations?

At least once in their career, nearly every safety worker in the utility business has been – or will be – faced with the need to use fall protection in an area where there is no place to tie off. In my role as a safety technician, I work with personnel in both generation and transmission business units; fall protection is needed in this line of work, but I have found that anchorage points can sometimes be few and far between. It’s a problem that clearly needs to be solved, and in this article I will share what my company has done to provide scenario-based solutions.

Scenario One
During an outage preparation meeting a couple of years ago, I was presented with some fall protection issues that employees had been dealing with. These issues specifically related to anchorage points for crews working on our main steam stop valves. Once the grating and I-beams were removed from the valve pit area, all potential anchorage points were eliminated, and thus no fall protection could be properly anchored and used in the valve pit area. Given this problem, I contacted a fall protection solutions group that came to visit our facility and gathered information regarding our anchorage concerns. While the solutions group was on-site, we also discussed possible recommendations to solve the anchorage problem. In a follow-up email after our initial meeting, the solutions group provided detailed information about the different types of equipment we could use to eliminate our anchorage issues on this particular project. The detailed equipment recommendations were then presented to our company’s personnel, and ultimately the decision was made to purchase the recommended equipment.

That recommended equipment was two advanced portable fall arrest posts, which allow us to provide overhead tie-off and utilize small self-retracting lifelines, or SRLs, so that workers in the valve pit are equipped with complete fall protection. Among the advantages of the portable fall arrest posts is how the posts are mounted. They offer several mounting applications that range from weld-on plates to beam clamps that are designed to fit 6-inch to 14-inch I-beams, meaning that we can use the posts in numerous locations throughout the company. Time and time again, the equipment has proven to be the solution to many of our fall protection needs in both generation and transmission work, including in Scenario Two below.   

Most utilities and contractors that perform work on energized conductors use some form of cover-up program or process. Culture plays a big part in how we currently cover for protection. When a new lineworker joins the crew, that person learns the ways of senior members of the crew, and later that knowledge is passed on to the next new person. Having control of what we work on also has played a significant role in how we cover. If you have control of the energized conductor or equipment you are working on, you may not need as much cover for protection, right? The problem is, in numerous cases, something unexpected has occurred, resulting in a flash or contact event.

There also are other reasons why we continue to have flash and contact events. Today, there is more work to do than there are qualified lineworkers available to perform the work, so sometimes companies advance lineworkers through the ranks faster than they would have in the past so those employees can perform energized work. In addition, we don’t have the luxury of doing as much de-energized work as we once did. Sadly, according to the U.S. Bureau of Labor Statistics, over a period of five years – from 2011 to 2015 – there were 62 fatalities related to electrical contact.  

So, what does all of this information point to? Simply put, it is time for us to take what we have learned from the past and train today’s employees on how to insulate (cover) for those times when things could go wrong. Then, if they lose control of what they are working with, no injuries will occur.

That’s easy to say, but changing a company or department’s culture is not an easy thing to do, especially when the company or department employs longtime workers who have found repeated success with the control-and-cover method. Many companies have spent countless hours and dollars to improve their cover-up processes – and many times observations and audits indicate their crews are working just fine – yet events continue to occur. It’s no secret that lineworkers deal with differences of opinion about how cover should be applied.

Over the past six months, three things have happened that I want to mention. First, I have answered numerous questions from clients and Incident Prevention readers regarding personal protective grounding (PPG). Second, the industry has experienced a rash of injuries and fatalities related to current in grounded circuits. The incidents most often have been associated with induction, but not always. And third, I have consulted with utilities and contractors, large and small, who are just now recognizing they have issues understanding PPG. It’s been hard to gauge the numbers – such as the frequency of incidents and especially comparing the seriousness of injuries – because there is no reliable clearinghouse for tracking incidents other than fatalities reported to the U.S. Department of Labor.

All of this is beside the real point, however, which is that there is no reason for any of these incidents to have occurred at all. Well, there is one: The utility industry is behind the curve in their understanding of the phenomenon of current in grounded conductors. There is an explanation for that, and it’s time to write about it again.

Let me be clear: The purpose of this article is to work toward solving the problem, not to find fault. To understand how we got to where we are, let’s first talk about industry awareness. Anyone who does research on the fundamentals of utility system grounding will notice that we have been struggling with PPG since as early as the 1950s. This has been documented in various papers from the IEEE archives of “Proceedings of the IEEE” – one of the first electrical industry journals, established around 1927 – and in “IEEE Transactions on Power Systems” since 1985.  

As the IEEE 1048 standard, “IEEE Guide for Protective Grounding of Power Lines,” points out in the introduction to the 2003 edition, “Protective grounding methods have often not kept pace with their increasing importance in work safety as the available fault current magnitudes grow, sometimes to as high as 100 kA, and as right-of-ways become more crowded with heavily loaded circuits, leading to growing problems of electric or magnetic induction.” Did you notice the date of the standard? The 2003 edition is a revision of the 1990 standard on protective grounding. As I stated earlier, we’ve been struggling with PPG since as early as the 1950s. Over 60 years is a long time to still not have figured it out.

In today’s electric utility environment, there are many training demands and opportunities due to new and inexperienced employees entering the workforce as older, more experienced workers continue to retire. New employees entering the field require – and are hungry for – information and hands-on experience, and they’re excited by the chance to engage in line work. To rubber-glove energized primaries and perform bare-hand transmission work is fascinating to younger workers and often provides them with an indescribable level of satisfaction and accomplishment. Ours is an exciting occupation, to say the least.

And yet ours also is an occupation that can be riddled with hazards. That’s why all of our employees must be given a strong foundation of skills training for their own protection. In our industry, many consider basic line skills training to be the most important type of training workers can receive, and I agree.

Considering recent annual accident totals reported by the U.S. Bureau of Labor Statistics, there is great reason for employers to be vigilant about the training of their workers. The electric utility industry suffered more than 40 fatalities in 2017 alone. Some of those deaths occurred because of falls and vehicle accidents, but a great number more occurred when an unprotected part of a worker’s body made contact with an energized conductor or piece of equipment. Phase-to-ground contacts that resulted in severe burns also were reported about once per week. These types of incidents are almost always preventable, so why do they continue to occur? Does it have something to do with training or human performance? Is there something else going on? 

Q: Recently an event occurred during a trouble job that surprised us. We had an underbuild phase down that was broken midspan. Our crew was working from an insulated bucket, and we grounded both the feeder we were working on and the one above. While our crew was beginning to crimp the splice for the repair, an energized line a few spans away came in contact with the grounded phase our lineman was in contact with. The lineman was in an insulated bucket, but he still received a shock. He was not seriously injured. Can you help us understand this?

A: The explanation is simple. Grounded circuits will still have current flowing through them if they are energized. Where there are resistances in parallel paths with the grounded circuit, there will be a voltage drop and there will be current flow through the parallel path. The current level is limited by the resistance in the path. Insulated bucket trucks are not totally isolating. To confirm that, all you have to do is look at the electrical tests performed on insulating booms. The current flow on an insulating boom is limited to a value well below the current necessary to injure a worker. In your case, there was voltage drop in the gap between the grounded, energized phase and the insulating boom that was a path to ground. Your lineman bridged that gap when he was in contact with the phase while standing in the bucket. The voltage was high enough to penetrate his skin so that current could flow. He was protected from injury by the current-limiting function of the insulating boom. We know it takes about 50 milliamps of current through a worker to rise to the level of injury. Depending on the electrical integrity of the boom and the voltage involved, there were – and this is just a guess based on boom-test protocols – perhaps 50 microamps to 1 milliamp of current that could flow on the boom. That is well below the level of injury. Electrical integrity of the boom is paramount in protecting workers. That is why it is critical to wash and maintain the boom.

I have fond memories of G.I. Joe. When I was a kid, I played with the toys and watched the cartoons. I sang along with the theme song and was ready to say “knowing is half the battle” in unison with the hero at the end of each episode, after Cobra had been defeated. The Joes were smart to realize that knowledge is power, and knowledge is especially powerful when it comes to safety, and more specifically, incident prevention.

Imagine for a moment what it would be like to know the future – think about how powerful it could make you. How much money could you make if you could predict winning lottery numbers or the winner of a sporting event? Think about all the undesirable outcomes you could avoid – such as getting injured – if you knew the exact date and time they were going to happen.

It’s unlikely you will ever know exactly what the future holds, but you can use human performance (HP) to predict, manage and prevent error-likely situations that could have led to incidents. In other words, the second principle of HP – that error-likely situations are predictable, manageable and preventable – gives you a crystal ball.

Let’s define what is meant by the term “error-likely situations.” These situations occur when error precursors are present and negatively impact decision-making. Error precursors, which are grouped into four categories – task, work, individual and nature – include such things as imprecise communication, departures from routine, distractions, inaccurate risk perception, overconfidence and time pressure (see more in the TWIN Model of Error Precursors sidebar).

Have you ever seen or heard a restaurant, vehicle dealership or retailer claim, “We care little about service”? On the contrary, don’t many of these businesses – if not most – make bold claims about the quality of their services? How many, though, take the time needed to do the work, pay attention to the details, and become known for meeting or exceeding their claims?

Now, think for a moment. Have you ever seen or heard an electric utility organization of any variety claim, “We care some about safety performance”? I doubt it. If you look at 100 electric utility website landing pages, it’s likely you will see slogans about safety. Investigate those sites further and it is common to see safety listed as a company value or guiding principle. Yet just as some retail establishments tout their high-quality service while acting in ways that make it clear that “service” is more a buzzword than a business practice, so, too, are there electric utility companies and contractors that publicly state their concern for safety while their day-to-day actions don’t back up those claims.

Job descriptions, job safety analyses, tailboard meetings, PPE and training are important components of an effective safety program. But even for companies that are truly focused on providing a safe working environment for their employees, there are at least three other components that contribute to a consistently safe workplace, yet tend to get overlooked: effective interviewing, onboarding and mentoring processes.

Have you ever questioned whether a contractor or subcontractor was qualified to perform electric power work? If so, you should consider developing a contractor safety management standard. This type of standard defines minimum safety requirements that contractors must adhere to when they perform work for your company.

Years ago, many electric power organizations used contractual language and a hands-off approach to establish contractor safety responsibilities. In fact, organizations hired contractors to perform work they felt was unsafe because they knew the contractor would do whatever it took to complete the job. These work practices have significantly changed throughout organizations that recognize employers share responsibility for working conditions and safety at multiemployer worksites. Utilities and contractors are adopting a shared commitment to worker and system safety within their organizations.

Regulatory Requirements
In the preamble to 29 CFR 1910.269 – the electric power generation, transmission and distribution standard – OSHA states the following: “When OSHA promulgates new safety and health standards, it does so against this background principle that employers share responsibility for working conditions, and thus for OSHA compliance, at multiemployer worksites. Therefore, when the Agency issues a new safety or health standard, it is with the intention that creating, exposing, and controlling employers at multiemployer worksites will exercise their respective responsibilities to ensure that affected employees are protected as required by the standard.”

While engineering controls are preferred over personal protective equipment for worker protection, many engineering controls, such as arc-resistant switchgear, require the purchase of new electrical equipment in order to fully implement them. When replacing equipment, this type of installation makes total sense, but it rarely can be the only company policy to mitigate arc flash in all facilities.

OSHA always prefers that organizations use the highest option possible on the hierarchy of controls. This is clear in the preamble to 29 CFR 1910.269, in which OSHA states the following: “NFPA 70E-2004 warned that ‘[d]ue to the explosive effect of some arc events, physical trauma injuries could occur’ … OSHA expects that the hazard analysis required by paragraph (g)(1) in the final rule will identify nonthermal hazards, including physical trauma hazards posed by flying debris, associated with employee exposure to electric arcs. … [OSHA requires] employers to address [these hazards] … [and] provide shields and barriers necessary to protect employees from physical trauma hazards. However, as noted by NFPA 70E, not all arc events pose physical trauma hazards from flying debris; therefore, this protection will not always be necessary …”

The 2018 NFPA 70E standard rightly took out the reference to 40-cal/cm² exposures posing a hazard from arc blast, since arc blast is more a function of containment and current than calories. In fact, our recent research surveyed the literature on arc blast pressure waves and found that many of the formulas did not come close to predicting our lab data from 4,000A to 12,000A (E. H. Hoagland, C. Maurice, A. Haines and A. Maurice, "Arc Flash Pressure Measurement by the Physical Method, Effect of Metal Vapor on Arc Blast," in “IEEE Transactions on Industry Applications,” vol. 53, no. 2, pp. 1576-1582, March-April 2017). New work continues to expand this knowledge and will be presented to the IEEE Electrical Safety Workshop this March in Fort Worth, Texas.

Knowing bucket capacity and understanding how to read a jib load chart are two critical elements of aerial device operation. While both tasks are fairly straightforward, it is crucial to stay within the allowable capacity of the unit. The platform capacity and material-handling capacity provided by the manufacturer are not recommendations – they are absolute maximum capacities that ensure the machine is not overloaded. Overloading equipment can result in overturning or boom failure. Equipment damage also may occur, resulting in costly repairs and a shortened usable life for the aerial device.

A fully equipped lineworker with PPE plus tools and materials for typical line maintenance can quickly add up to 700 pounds or more for distribution work, and upward of 1,000 pounds for transmission work. Bucket capacity is identified on the ID plate and inside of the basket on most aerial devices. In addition, be aware of dual-rated buckets with different capacities based on configuration and use as a material handler; these types of buckets are available from some manufacturers. Before climbing in, lineworkers should verify that their weight – in addition to the platform liner, if used, and all of their tools and equipment – doesn’t exceed the bucket’s capacity.

“Don’t forget to account for boots, harness, tools and any components you may add to the bucket once you are elevated,” said Kyle Wiesner, aerial products engineering manager for Terex Utilities. “Tools such as phase lifters, crimpers, hydraulic drills or chain saws all add up. Weight of personal clothing can change with the weather, so don’t forget to recalculate come winter. If a component is in the bucket while work is being performed, that weight needs to be factored in as well.”