Ideas about how to work safer, better, faster and easier are bound to come up when dedicated utility professionals get together to swap stories from the front line. The groundbreaking long-line work method in use at Pacific Gas and Electric Co. (PG&E; San Francisco, California, U.S.) got its start during informal conversations between a lineman, a work procedure specialist and a helicopter pilot.

PG&E employs both energized and de-energized work methods as it maintains and operates more than 18,000 circuit miles (29,000 km) of transmission line. This utility keeps the lights on for approximately 13 million people in northern and central California. Concerns for the environment and endangered species require constant vigilance to go beyond conventional methods to reduce or eliminate the impact of trucks and equipment on the land. With northern California's varied terrain, physical access is often a challenge for midspan repair or replacement work. These concerns led PG&E to look for a nonconventional work method for challenging access issues, multiple work locations and areas with potential environmental impact.

MOTIVATION

PG&E lines span 70,000 sq miles (180,000 sq km) of land and have been built over the past century. Many lines are in hard-to-reach areas that can take days to get workers and equipment into place to begin work.

Initial discussions focused on how to work on inaccessible facilities while reducing the hazard to workers. About 14 years ago, PG&E work procedure specialists and linemen Chuck Stinnett, Tom Rasler, Joe Hemstock and Bob Sholler were talking to Mark Gunsauls, pilot and owner of P.J. Helicopters (Red Bluff, California), about ways to use helicopters to safely and easily place employees at exact work locations. Gunsauls explained to the PG&E group how the external long-line method had been used to transport law-enforcement agents into specific areas that were otherwise inaccessible. Why couldn't PG&E do the same to position line workers in midspan and to transport workers to structures?

Gregg Lemler, director of Transmission and Substation Maintenance and Construction, saw the potential of this work method and encouraged the team to forge ahead. Lemler recalled, “When I saw what the team was proposing, I knew that we had a safe way of solving our access problems. At the same time, we could improve our grid availability for customers and reduce costs. A win-win for everybody.”

DEVELOPMENT

Soon, the IBEW Local 1245 got involved with PG&E, and the PG&E Barehand and Helicopter Working Committee began work on the development of the procedure. Committee membership includes linemen, transmission troublemen and transmission line management. The committee's purpose is to develop safe work practices and tools for both conventional and barehand workers. The long-line work procedures and equipment in their present configuration were developed and refined by the committee.

During the design phase, it quickly became obvious these new methods were safer for the line worker, and accessibility and terrain issues were avoided, thus decreasing any impact on the environment. They are also easier for the worker, because there is less physical and mental strain than that produced by climbing towers or riding in a conductor cart.

With workers closely involved in the design, PG&E developed safe, efficient, effective and accepted work methods. Many workers who enjoy the exhilaration of helicopter work actually prefer these methods. After a recent demonstration of the technique, troubleman Russ Rylee stated, “It doesn't matter how many times you do it. It's a great time to be a lineman.” From seasoned linemen to relative newcomers, one often hears remarks like: “It reminds me of how I felt as a first-step apprentice lineman. All of that adrenaline feels great!”

THE WORK METHOD

In the long-line work procedure, the worker is suspended in a harness or boatswain chair beneath the helicopter on an external 8-braided standard nonconductive rope. This procedure is used to perform barehand, de-energized and midspan work, or to transport workers to structures. When in an electrical environment, the workers wear barehand suits with flight helmets embedded with radio communications. Bonding wands are unnecessary because of the minimal mass represented by the worker that must be brought to the same potential of the line.

Many of PG&E's barehand and helicopter work procedures are designed for efficiency, using two workers. As a result, PG&E created a new two-person boatswain's chair. The Federal Aviation Association's (FAA) Flight Standards District Office reviewed and approved this flight procedure. As a result of the FAA filing, the FAA added specific language to its rules allowing utility workers the use of the external load application. Cal/OSHA, which is responsible for enforcing California laws and regulations pertaining to workplace safety, also approved PG&E's application to include this work procedure in its barehand variance within the state of California.

MEASURABLE SUCCESS

PG&E used these work procedures consistently throughout 2006 with tremendous success, both in energized and de-energized environments. During the year, there were several large reconstruction projects (insulator replacement, reconductoring and tower modifications) in which workers, equipment and materials were transported utilizing the long-line method.

Additionally, PG&E performed various other projects such as insulator replacement, hot-end hardware replacement and midspan repairs. Some projects were located in environmentally sensitive land such as the San Francisco Bay Waters. Estimates of labor savings are between US$1 and $2 million for 2006.

Lineman Ken McClure, who was responsible for the Sky Chair's detailed design, confirmed the cost savings. “Typically, we've seen the ability to save 50% on average in labor costs using this method versus traditional methods,” said McClure. “Jobs where once we'd have to walk in with a heavy crew (between 10 to 15 workers) can be done in about two hours using this procedure — and the line would never need to be out, avoiding inconvenience for our customers.”

PG&E's Working Committee, whose members credit PG&E's leadership with offering substantial support, was instrumental in the innovation of the ideas and subsequent detailed development of the long-line method.

The industry had a chance to see this work method in action at the 2006 IEEE ESMO Conference at Public Service of New Mexico's facility in Albuquerque last October. Typical crowd response to the introduction and demonstration of the work method included phrases like, “Awesome!” and “Cool!” Presently PG&E is the only utility in the country known to use the external long-line work procedure for both de-energized and energized work.

What's next for PG&E's Working Committee? You might have to listen in on one of those lineman conversations to find out.

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Kris Buchholz earned BSEE and MBA degrees from the University of California at Berkeley. Her professional experience includes electric T&D operations, engineering and construction, gas construction, telecommunications and customer field service. She currently serves as director of Electric System Operations at Pacific Gas and Electric Co. in San Francisco, California, U.S. Buchholz is a registered professional engineer in California, a past chairman of IEEE Engineering in the Safety, Maintenance and Operation of Lines Subcommittee and a member of the Western Electricity Coordinating Council Operations Committee. KKB1@pge.com

Chuck Stinnett has worked for Pacific Gas and Electric Co. for 34 years. His professional experience includes electric T&D line work, design of work methods and tools, and training. Stinnett is responsible for helicopter pilot certification for working in a wire environment, as well as for all work procedures related to barehanding, live line, rigging, rubber gloving and helicopters in an energized work environment. He has been a lineman, foreman, instructor, supervisor and superintendent, and he currently serves as standards and work procedures supervisor. CNS1@pge.com

John Parks began his career with PG&E almost 30 years ago and has held various positions including journey line worker, front line supervision, T&D pole-replacement manager, manager of gas and electric training, distribution gas and electric superintendent, and manager of T&D electric maintenance. Parks is currently the superintendent of PG&E's overhead and underground electric transmission maintenance and construction department. JLPD@pge.com

Libby O'Connell is the project manager of PG&E's publications for internal communications, and provides content management, writing and editing for the company Intranet site and monthly employee newsletter PG&E @Work, distributed to PG&E's 20,000 employees. She also publishes a monthly issue for the company's 19,000 retirees. ExO5@pge.com

BAREHAND AT PG&E

In the early 1990s, PG&E began using barehand-work procedures on voltages up to 500 kV. The procedures used — barehanding from an aerial device or from a work-positioning ladder located on the tower — were typical for the industry. Over time, there have been increased pressures to keep lines energized, limiting time windows for maintenance outages and reducing opportunities to work de-energized lines. While the barehand procedures have proven to be highly safe and efficient, PG&E felt the need to explore other ways of performing more energized work in areas where vehicle access is limited and land is environmentally sensitive.

The long line has an extensive history in military, law enforcement and firefighting, and has proven to be extremely safe and efficient. PG&E took the concept of long line to a new level by employing several techniques, tools, equipment and extensive training for line workers and helicopter pilots. The company has developed long-line methods for barehanding all transmission voltages from 60 kV to 500 kV.

Early in the development stages, the PG&E Working Committee looked at linking “hot sticks” together to sling workers from. While the hot sticks possessed the mechanical and dielectric properties desired, the potential for leakage across the sticks from humidity and/or alloy transfer in the event the sticks contacted aluminum conductors was an unacceptable risk. PG&E has many years of experience with “hot rope,” and the company's line workers have come to trust rope integrity, both from strength and insulation aspects. The rope and associated attachments undergo rigorous testing, challenging mechanical and dielectric properties.

FIRST DESIGNS

The concept for the long-line work process began in the 1990s, and PG&E has had a Joint Committee with the IBEW Local 1245 since the inception of the original barehanding idea in the late 1980s. The committee has had a longstanding membership including management and union representation. All decisions are made collaboratively — working collectively on ideas, and considering all potential obstacles, pitfalls and benefits.

PG&E's management regards the leadership that the IBEW Local 1245 has provided as essential to the success of the procedure. Only after years of experience did the committee members feel enough was known about the helicopter's capabilities and potential, and the skills required by pilots to move forward with the procedures.

P.J. Helicopters (Red Bluff, California, U.S.) did much of the helicopter adaptation research and development. P.J.'s management dedicated many of its own resources and knowledge to develop the tools and equipment associated with helicopters for this procedure. All of the pilots employed by P.J. Helicopters attend the training with PG&E line workers. PG&E recognized the value of pilots learning alongside line workers during both classroom training and the actual field application very early in development. The relationship with P.J. Helicopters has been as important as the partnership between PG&E and the IBEW Local 1245.

Safety has always been kept in the forefront as the guiding principle from the development of the first concepts, and is always the first priority in all work procedures. The committee also kept the comfort of the line workers and pilots in mind — in order for the procedure to be embraced, workers would not only need to know it was safe, but that they would be able to perform it comfortably.

The first design involved working from a body harness; however, during the initial design process, suspension trauma (to which the lower body is exposed when hanging from a harness for extended periods of time) was not taken into consideration. A new type of harness designed with line workers' comfort and suspension trauma in mind was then purchased from the Yates Company. However, even with this model, workers' time in the harness suspended from the helicopter should not exceed 30 minutes. PG&E's first trials on de-energized lines proved very successful — but again, due to suspension concerns, short-duration projects limited the work procedure potential.

One of PG&E's committee members developed a device dubbed the PG&E “Sky Chair.” Working with Yates, the utility developed the chair, which can be used singly or in tandem, in which line workers sit comfortably suspended from a long line below the helicopter, eliminating concern about suspension trauma. PG&E line workers have successfully completed projects during which line workers are in the air for several hours a day with little or no discomfort.

One recent example of a successful project was a three-person line crew that replaced 120 dampers on 20 miles (12.4 km) of an energized 115-kV line in Northern California. The towers were located in remote areas, which would have been extremely difficult to access with traditional line crew vehicles. The crew completed the job in 12 crew hours. Two line workers worked through the project transported via helicopter to the work sites to replace dampers. The average time to replace each damper was about four minutes.