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Electrocuted? Clarifying Terminology & Being Vigilant About Electrical Safety

Avoiding being too complacent about electrical safety when we should really be more careful.

“You keep using that word. I do not think it means what you think it means.”—Inigo Montoya, The Princess Bride

The Twitterverse was hopping a while back with news of Canadian singer Grimes being “electrocuted” during a concert in Dublin. (Go here and #Grimes on Twitter.)

While she was shocked on stage, she definitely wasn’t electrocuted multiple times. That’s because the word “electrocution” refers to death by electric shock. If she was indeed killed by electric shock and brought back to life multiple times to keep performing, that must have been one heck of a show. Sort of like Frankenstein’s monster playing backup keys for your band (now that’s a show I would pay to see).

So how did we get here?

Mostly, it’s the media. Not a day goes by that I don’t read or hear some misuse of words about electricity in both mainstream and alternative media. Whether it’s a it’s a TV report about street poles with “current on them” that spark when rubbed with a screwdriver or reporting about being safe from lightning striking a car because of “rubber tires insulating you from the ground,” it’s just plain incorrect information that feeds the “old wives tales” factory.

To set the record straight, we are quite safe from lightning strikes in our (non-convertible) vehicles due to the Faraday Cage created by the car metal surrounding us. That’s what bends the electricity around the occupants, keeping them safe if a lightning bolt hits the vehicle. Of course, you don’t want to have your hand stuck outside the window in a lightning storm, because you’re no longer inside the cage and you’ll likely be electrocuted. And yes, I mean killed by electric shock.

So what did happen to Grimes? Well, there must have been something on stage that wasn’t properly grounded. (The report linked above attributes the cause to a “malfunctioning pedal.”) The lack of electrical grounding allows a normal AC power leakage current to create a voltage bias on a piece of gear (guitar, keyboard, microphone, etc…).

If you get between this electrically “hot” gear and something else that is properly grounded, that’s when you feel a shock. Depending on the voltage, how wet your hands are, and the source impedance of the fault current, you’ll either be shocked, knocked unconscious, or possibly even electrocuted (again, killed by electric shock). Check out this drawing for a real 18th-century experiment about feeling electrical shocks:

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Aren’t all stages electrically safe?

Well, they should be, but sometimes there’s a monkey wrench thrown into the works. For instance, I’ve had a number of artists show up on stage with a cool vintage guitar amp they bought at the local pawnshop. While it might sound great, it could very easily have a broken or missing ground wire on its power cord. Normal leakage currents can turn into AC bias voltage on the chassis of these backline amplifiers without a proper ground path to drain away these voltages.

However, as long as the musician is touching only their guitar and not a grounded mic at the same time, they may never know that their body was electrified to 120 volts (or 230 volts in Dublin). That is, until the moment when they’re touching both their guitar and their microphone at the same time. That’s when a fault current will flow through their body on its way to “ground.”

While a broken extension cord or power plug can easily cause this “hot-chassis” condition on a guitar amp, it’s also possible for the outlets in the wall to lack a proper safety ground, and even a professional power distro can have improperly grounded outlets due to improper hookup or lack of maintenance.

Electricity is bi-directional, so it really doesn’t matter if the fault current flows from the mic through you to your guitar, or from the guitar through you to the mic. Either way, you can get a substantial shock that can electrocute (kill) you under the right circumstances.

There have even been a number of electrocutions of pastors in baptismal pools holding a hard-wired microphone. In one case in Texas, the microphone was indeed properly grounded, but the water heater in the baptismal pool had developed a crack in its hermetically sealed cartridge, and the water was biased to around 90 volts AC. It also appears that the GFCI (Ground Fault Circuit Interrupt) circuit breaker was improperly installed so it wouldn’t trip when it detected a fault current.

When the pastor was handed a grounded microphone, electrical current flowed from the water through his heart, into his hand, out through the microphone and into the building ground. Yes, he was indeed electrocuted (killed) by electricity. The lesson here is that anyone standing in water should only use RF (wireless) microphones.

As a side note, I was teaching a class at a church 10 years ago when someone asked about feeling shocks from water puddles surrounding a baptismal pool. They said these were all 120-volt lights under the floor, and the gaskets must have failed, allowing water on the floor to infiltrate the seals. The congregation was feeling shocks when they stepped into the water puddles, and the technician was wondering if this was dangerous.

I told him it needed to be corrected immediately, but he said they weren’t in a big rush to fix it. The church maintenance guys told the members to hop on one foot when they got out of the water since they only felt the shock when stepping out with both feet. I am not making this up. The takeaway is that if you feel any kind of shock while you’re in water, it’s time to reverse course and get the heck out of there.

So how do we check for this invisible electrical assassin?

Well, a device called a Non-Contact Voltage Tester (NCVT) that can be purchased at any big box store for less than $20 provides a quick way to test backline amps and microphones for a hot-chassis voltage.

And even though it’s not being enforced in all jurisdictions, the National Electrical Code does indeed require GFCI outlets for any outside stages, and may soon be requiring it for inside stages as well. Properly installed GFCI receptacles have and will save lives. So don’t bypass them if you encounter one on stage. And if a GFCI trips, that’s an indication that something has gone wrong with the gear and dangerous voltages are on the loose.

Just be aware that any electric shock is proof that a safety ground wire has failed somehow and is allowing dangerous voltages to appear on your gear. So if you feel a shock from a guitar or microphone (any kind of shock), then it’s time to find out the reason and get it fixed immediately.

And if you hear or read a reporter discussing how someone was “electrocuted” at a concert but is still alive to talk about it, contact the media person and/or organization and refer them to this article. I think that we all get way too complacent about electrical safety when we should really be more careful. Few consumers will ever put themselves in the dangerous positions that performers and sound technicians find themselves in every day when they’re surrounded by all sorts of electrically powered gear.

Let’s play safe out there…

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