There are a number of hazards unique to substations. The substation safety information found in this article is drawn from 30 years of personal experience as well as industry best practices, regulations, codes and company policies. During my time working in substations, I have seen some horrible accidents and hope the following lessons I’ve learned will prevent other people from having to experience injury or death.
According to The Humane Society of the United States, there are approximately 78.2 million owned dogs in the country and about 40 percent of all households have at least one dog. Of course, the percentage of households with dogs is higher in suburban and rural areas than in cities, but the fact remains that dogs are nearly everywhere. Couple these statistics with the fact that most households with dogs also have electric service, and those of us who work in the transmission and distribution departments of electric utility companies have a potential problem. OSHA would consider dogs a recognized workplace hazard, right?
The minimum approach distance (MAD) is the closest distance a worker is permitted to approach an exposed energized conductor. When we think of MADs, we normally think of qualified electrical workers, and this discussion will cover what a MAD is, how it is developed, how it is to be applied and how it is often misapplied. There is also a second MAD for nonqualified electrical workers known as the 10-foot rule. Nonqualified electrical workers, subject to federal OSHA regulations, must remain a minimum of 10 feet away from any exposed energized conductors or equipment up to 50 kV, plus an additional 4 inches for every 10 kV above 50 kV.
Both the NESC ANSI C2 rules and OSHA regulations require signs at appropriate places around utility facilities and workplaces. ANSI Z535 standards that specify the attributes of appropriate safety signs and labels for utility use include ANSI Z535.2: Environmental and Facility Safety Signs, ANSI Z535.3: Criteria for Safety Symbols and ANSI Z535.5: Safety Tags and Barricade Tapes (for Temporary Hazards). The coordinated ANSI Z535 criteria apply to every temporary or permanent safety sign or tag on a utility system.
The threat of high-voltage electrical contact is very real for emergency first responders who are called to the scenes of accidents and other unplanned events. The safety of the public and our emergency workers should be a top priority.
“You fight the fires, we deal with the wires” is a theme that is stressed in the comprehensive outreach program created by NSTAR, a Northeast Utilities company based in Boston. Contacting the utility company first, before any actions are taken by responders, is essential when dealing with an invisible force that travels at 186,000 miles per second. If you make a mistake at the office, you can use an eraser or the delete key to correct it. In the field, there is no forgiveness and a split-second error in judgment will likely lead to an irreversible result.
You’ve said it and heard it many times before: “Accidents happen.” It’s a phrase that essentially allows us to admit that accidents can’t be prevented. In business, that attitude has the potential to breed complacency when it comes to worker safety. A zero injury philosophy, however, maintains that there always exists some combination of tools, work practices and personal protective equipment that enables workers to carry out their assignments without being injured. Consequently, striving for zero injuries makes sense; it is a practical, achievable goal.
The line crew’s job for the day is to replace a 115-kV wooden H-frame transmission structure. No problem – this crew has done this type of work a number of times in the last few years. Upon arrival at the job site, the bucket truck and crane are arranged according to the job plan. A tailgate safety meeting is conducted, during which the clearance is reviewed and the points of isolation are identified. The work procedure is analyzed, including a discussion of the possible hazards and grounding plan for this work site. It is noted that, although not visible from this work site, this transmission line does share a right-of-way with two other high-voltage transmission lines about 15 miles from the work site. Induction could be an issue on this job. Maintaining a proper equipotential zone is emphasized.
Following is a treatment of the complex subject of enclosed space rescue and it's a lot of information. I would like to just tell you what to do, but there is no single solution. Your background understanding of the relative standards, interpretations and directives is necessary for you as trainers and administrators to mount an effective enclosed space program.
Ferroresonance is a complicated issue. It is important to familiarize crews with ferroresonance because as the number of URD systems installed increases and as systems age, the incidence of ferroresonance increases and so does the threat to equipment, service reliability and, most importantly, the safety of workers and customers.
The electric utility industry is loaded with potential hazards. Climbing at heights is one of those inherent safety risks that come with the job. At Louisville Gas and Electric (LG&E) and Kentucky Utilities (KU), we require 100 percent fall protection on poles and towers for our employees and business partners. This policy is part of our “no compromise” approach to safety and supports our belief that we can leave nothing to chance when it comes to the well-being of our workers.