System Operations: Who’s in Charge?
System and utility operators are required by OSHA 29 CFR 1910.269(m) to have a procedure to de-energize their systems for protection of the employees working on those systems. The rules in 1910.269(m) do not specifically require a written procedure, but it is hard to imagine how an effective procedure could be maintained if it weren’t written. Unlike lockout/tagout, we refer to these programs as switching and tagging. Switching and tagging apply to transmission and distribution, including substations. The 1910.269 standard has a paragraph (d)(2) on energy control procedures for power plants that is much less rigorous than the traditional lockout/tagout for general industry found in 1910.147, “The control of hazardous energy (lockout/tagout).” Part 1910.147 specifically exempts “installations under the exclusive control of electric utilities for the purpose of power generation, transmission and distribution …”
Most substation entry and system control centers also have additional rules they must adhere to per the North American Electric Reliability Corp. (NERC) and the Federal Energy Regulatory Commission (FERC), including those pertaining to security and reliability of the bulk power systems across the U.S. and Canada.
Daily operations of utility systems are the responsibility of the system owner or their designated operator. Whether working overhead or underground, switching system operations also are under control of the system operator. In underground, some system operators will allow switching orders to be written in the field by authorized employees when switching on single-phase loops. Other companies require all switching orders to be written, reviewed and dispatched by a system operator, and the operator will issue a clearance when needed. With trouble cases, a field-authorized employee will take a clearance at a riser pole, and the operator will then let field personnel write, review and execute the switching order.
The employer is ultimately accountable for employee safety and to NERC/FERC for the reliability of system switching when transmission switching can affect the interconnected systems if something goes wrong. Yet with all of this regulation, it can be extremely easy to lose sight of the safe and correct operation of utility systems. I’m familiar with a recent incident during which severe injuries occurred at a substation. After the OSHA investigation, it was discovered that the operator had no written electrical safety program nor any equipment-specific written lockout/tagout energy control policy for the substation. It turned out that the system owner had been operating in this manner for years with no incidents. The important takeaway here is that worker training, written policies and an understanding of what the regulations require will prevent many incidents from happening at all.
To illustrate the importance of attention to detail in systems operation and switching work, I would like to review a few other accidents with which I’m familiar. These are accidents I helped investigate and/or gave depositions about, almost all of which involved injuries or fatalities. Each of these incidents also was found to be preventable if proper measures had been taken, OSHA regulations had been followed and hazards had been identified.
Keep in mind that when switching any part of the integrated electric grid, OSHA’s regulations are quite specific, requiring the system owner to assign an operator to ensure the reliability and dependability of the electric grid. If an operator is not available, the person in charge of the work task then becomes the system operator. Switching orders should be originated, reviewed, dispatched and executed by qualified, authorized employees in the field. For contractors working on utility systems, the host employer will make the decision as to allowing contractors to switch. Some companies do, others do not. Certain utilities have a dedicated list of authorized employees who can perform switching on the system. If your name is not on the list, you cannot switch.
Numerous incidents have occurred due to errors in writing, reviewing and executing switching orders. In one of the incidents that I’m familiar with, the originator of the switching order completely left out a step, so no one opened the disconnects to prevent back-feed into the station once the load was switched in the field to other circuits. The employee who reviewed the order prior to dispatch and execution failed to discover the mistake. All load was off the substation in question; all breakers were opened; all switches isolating the breakers, regulators, AIM switch and bypass were opened and tagged; and the station power transformer bank was de-energized, checked for the absence of voltage and grounded. The four distribution circuits had no load and were isolated from the station. The problem was that, in two different stations, which were in two different states hundreds of miles apart, no one cut jumpers or opened gang switches feeding back into the station. The task was to work on transfer bypass switches on top of a frame that was still energized, and a 12.4/7.2-kV contact was made by a contractor.
A similar situation occurred involving a circuit in a small substation at a generating plant. An employee was cleared to work on a switch, and there was back-feed to the switch from another auxiliary generator that was running to peak shave the load. This was an unusual arrangement yet a normal operation for the employees, but this time they did not follow safety procedures. A terrible accident occurred on a 25-kV system. After the investigation, it was discovered that the written lockout/tagout plan was not accurate and did not meet OSHA 1910.147 or 1910.269(d) or (m) standards.
In another incident I’m aware of, a switching order was missing a step to clear a UD feeder that allowed back-feed from the closed loop in the field. Someone noticed that one circuit was not grounded as the other circuits were. Rather than check for the absence of voltage, the employees attempted to ground the energized cable, which resulted in a flash and the lockout of another breaker. Thankfully there were no injuries.
Don’t Fall into the Trap
Most utilities and system operators have formal switching training and programs that incorporate human performance tools and processes to help cut down on switching errors. But when we’re in the field following dispatched orders and performing switching procedures, we can still fall into the trap of thinking everything is going perfectly well. Most of the time it is. However, if something seems wrong, we need to stop. Sometimes it’s a good idea to slow down or stop even if everything seems right. Take the time to double-check the work that’s been done and the steps that are coming up next. Given the speed at which the industry and its employees continue to change, it is well worth the time spent to question and verify everything when it comes to system operations and switching work.
About the Author: Danny Raines, CUSP, safety consultant, distribution and transmission, retired from Georgia Power after 40 years of service and opened Raines Utility Safety Solutions LLC, providing compliance training, risk assessments and safety observation programs. He also is an affiliate instructor at Georgia Tech Research Center OSHA Outreach in Atlanta.