Stray voltage: Hidden danger that can strike from everyday objects
Nov. 13, 2014 at 7:39 AM ET
On May 5, 2006, 14-year-old Deanna Green was about to go to bat in a church softball game in a Baltimore park when she touched a metal safety fence. She was killed by 280 volts of electricity leaking into the fence from a damaged underground cable.
Last year, the city of Baltimore finally reached a $200,000 settlement with Deanna’s parents, former Baltimore Colts defensive lineman Anthony “Bubba” Green and his wife, Nancy. That followed an undisclosed 2010 settlement with the private contractor responsible for power lines in the park. “Unless you’ve seen your child electrocuted right before your eyes, you can never know how I feel,” the Greens wrote in the Huffington Post.
On Thanksgiving Day 2010, Lisa McKibbin was walking her 68-pound German shorthaired pointer Sam through a Seattle neighborhood when the dog stepped on a metal plate by a lamppost and was electrocuted. “I had no idea what was happening,” McKibbin said. “All I could think of [was] he was having a heart attack, he was seizuring. I opened up his mouth, stuck my hand in his mouth and I received a jolt … I received a jolt of electricity in my hand.
“He passed within a couple of minutes,” McKibbin added. “Sam meant the world to me. He was my soul mate dog.”
In both cases the culprit was stray voltage, which can make everyday objects — even ones that aren’t metal — come alive with electricity. It happens because many cities and towns use old wires to conduct electricity. With the insulation eroding away, voltage from inside can leak out everywhere.
“Sidewalks, manhole covers, roadways, fences — anything that’s in our landscape that has wires buried underground: When they fail, they leak to the surface,” explained Dave Kalokitis, chief engineer for Power Survey Company, a Kearny, New Jersey-based company that power companies hire to help detect what are known as contact voltage hazards.
Stray voltage can be an invisible killer. “When a water system breaks down, you see a puddle,” Kalokitis said. “When a gas system breaks down, you can smell the gas leaking. Electricity, there’s no telltale.”
To demonstrate the problem, Kalokitis and engineers from Power Survey took the Rossen Reports team along as they scanned for stray voltage at night in Washington, D.C. (Power Survey was not under contract to the District of Columbia or any of its power companies as it conducted the demonstration). Right away, sensors in Power Survey’s specialized truck detected a hidden hot spot in a streetlight.
Kalokiitis touched a lightbulb to the streetlight. “When I take this household lightbulb and make contact to it, the lightbulb lights. The same voltage you would find in a light socket is on the outside of this streetlight,” he said.
Employing a screwdriver, Kalokitis added: “Just to show you how much power is here, I’ve grounded the screwdriver and when I touch it to this pole, you can see the sparks that fly from this.” Power Survey immediately blocked off the area and called the city to report the danger.
Minutes later, the team found more problems in an area where streetlight after streetlight sparked up. Even the sidewalk was electrified with over 90 volts.
“If this is so common, why aren’t people dying from this every single day?” Rossen asked.
“Well, a couple of things have to happen to get a shock,” Kalokitis replied. “You have to touch it. And if your feet are wet, it’s particularly dangerous.”
“Why do we see pets getting hurt?” Rossen asked.
“Pets don’t have the protection of shoes, so their bare paws are touching the ground and the electricity could pass right through their body,” Kalokitis said.
At a bus stop, even a regular schedule sign was sparking up. “There are wires buried underground, and this pole is driven into those wires,” Kalokitis explained.
In one night the team found more than 40 locations with stray voltage in Washington, D.C., alone. Power Survey engineers say power companies aren’t doing enough to keep the public safe.
“It’s a very reactive situation,” Kalokitis said. “So usually after a death or an injury, there’s testing, but prior to that, nothing happens.”
Power Survey says less than 2 percent of cities across the country are testing for stray voltage. Rossen Reports reached out to trade groups representing the power industry for comment and they declined, although the Electric Power Research Institute, a research organization that does not represent the industry, issued a statement (see below).
The best way to protect yourself is to avoid touching structures like lampposts and hydrants and walking on manholes. And if you receive a shock, call and report it immediately.
Statement from the Electric Power Research Institute in response to this report:
“The Electric Power Research Institute (EPRI) conducts research on the utility industry for the public benefit. EPRI’s effort in stray/contact voltage is focused on the safety by developing assessment methodologies for a variety of stray/contact voltage conditions and to provide the industry effective prevention tools, both to mitigate current risks and to prevent future occurrences.
EPRI collaborates with the Institute of Electrical and Electronics Engineers (IEEE) Working Group, a center for industry coordination on stray/contact voltage. Our ongoing research (20 years) helps to apply new knowledge and technology to prevent, detect and solve stray voltage occurrences. EPRI maintains an informational website at http://strayvoltage.epri.com
Utilities have worked with EPRI to develop information forums, research programs, test protocols and stray/contact voltage detection equipment. Utilities and EPRI support the annual conference on the issue — the Jodie Lane National Conference for Stray Voltage Detection Prevention and Mitigation.
The detection of stray voltages can be effective even for small levels if the object or area that is energized is sufficiently large. These incidents are more common at splice points in older underground wire installations.
EPRI is a scientific and technical research organization. It does not provide opinion or conjecture on any individual electric utility regarding test practices or procedures. Questions concerning individual electric utilities should be directed to those companies or to their regulatory organizations (Public Service Commissions), which keep data on stray/contact voltage occurrences.”
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