Ooops!
CNN.com – Pastor electrocuted while performing baptism – Oct 31, 2005 — I’d like to know how an audio mike can kill you? Any EE’s out there to clear this up?
WACO, Texas (AP) — A pastor performing a baptism was electrocuted inside his church Sunday morning when he adjusted a nearby microphone while standing in water, a church employee said.
The Rev. Kyle Lake, 33, was stepping into the baptistery as he reached out for the microphone, which produced an electric shock, said University Baptist Church community pastor Ben Dudley.
Water in a baptistery usually reaches above the waist, said Byron Weathersbee, interim university chaplain at Baylor University.
Lake was pronounced dead at Hillcrest Baptist Medical Center, nursing supervisor Pat Mahl said.
“I’d like to know how an audio mike can kill you?”
That’s easy. The mic wasn’t properly grounded AND he was standing in water. If you look through the history of rock and roll you’ll learn than dying from an ungrounded mic is more common than you’d think.
I am a EE. But that does not mean that I can explain what happened. There are two kinds of microphones. Dynamic and condensor. A dynamic microphone is usually the larger hand held style. The condensor mic is usually the smaller lapel or hanging mic that is over the choir group. Only the condensor style has any electricity supplied directly to the mic. This is usually in the range of 20 to 48volts DC not AC and the current is on the magnitude of 2mA. It actaully only takes about 500mA to cause death. Here again this would require AC current. Neither mic is normally subjected to this type of electricity. One thing that most people do not uderstand is that if there is another source of the AC current such as an underwater light? That if the Baptismal is not grounded then you could be touching a bare 115v ac line and not be affected. As soon as you touch the grounded mic over your head, then the current can complete its path. Just something to think about. This does not preclude that there could have been redundant failures within the PA system that may have caused the Mic to have AC voltage present, but usually this would require multiple failures to occur. I only hope we are told what happened in the end. I would hate for this to happen to someone else.
He also had a 5 year old little girl and 3 year old twins. Very, very, sad.
Well…I would say it’s not quite that easy… Microphones use a very small AC voltage to transmit sound which in and of itself should NOT be a problem so I have two theories about this.
1) There is a system for the transmission of DC power to a microphone (48v) over the same wires normally used for audio which could be a problem but is also unlikely because it’s still afairly small amount of power.
2) The more likely situation is that some regular 120v AC got mixed in somehow. It’s not as uncommon as you might think. I personally have found that a microphone installed on a metal lectern that also had a reading lamp had a short in the reading lamp, electrifying the microphone which gave me a shock. There could also be a short in the sound system somewhere which sent high power through the grounding shield in the cable and into the microphone body.
It’s one good reason to invest in some wireless micrphones if you’re working around water.
Ben Franske I played guitars in numerous bars in the 80s and 90s where I’d get shocks from both the mics and my guitar. It’s very common. Here’s a website of dead rock stars, and three died of electrocution in the 70s alone.
http://www.geocities.com/trcoleman.geo/dead_musicians/Year1970.html
I think the sole reason more people don’t die from it is because we’re not standing in water, i.e., acting as a ground, when we’re touching mics like the moron was in this incident.
Hey, Imafish. The guy’s dead, no need to insult him. Given that there are probably tens of thousands of baptisms happening every week, with a high percentage using a microphone near the water, and this is the first time I’ve ever heard of someone dying from it…well, you can’t blame the guy for not thinking about it. If anything, it’s the sound guys’ fault for not knowing about and taking steps to prevent something like this.
Imafish : I am trying to search for the proper word to label you for referring to this Priest as a “moron” ::: alas, I have failed; however much I desire to label you “pond scum” – good taste is preventing me from doing so. Tragic Accident indeed.
It is likely that the mike was plugged into an amplifier that was not properly grounded because it did not have a transformer power supply and/or had a defective power cord and/or someone cut the grounding pin off the AC plug or used an adapter. Result: the amplifier chassis was electrically elevated above ground. Because the microphone case was connected to the chassis, an electrical path was formed from amplifier through the gentleman to ground. Sadly, 3 mA is enough to disrupt heart action and if my theory is correct, the only protection was the circuit breaker on the wall – at least 15 amps.
Ground Fault Interrupter (GFI) outlets like the one in a modern bathroom are designed to prevent this problem.
I have looked at your web site suggesting microphones have killed musicians. I must admit several have had very misfortunate ends but the only electricutions that I saw were from electric guitars. Not microphones. This does not preclude that it could not happen. A series of faults would have to occur which in the world of engineering does not prove out as a probable solution. Usually electrical failures are due to single faults. Hence the argument for the mic to be made hot through the ground circuit would require two redundent failures to exists. 1) that 115vac has some how come in contact with the DC circuit of the microphone and 2) the existing ground has failed or been lifted such that the 115vac circuit could not blow its own breaker. Here again there are several outcomes that may have actually caused this terrible accident. I hope that we do find the answer so that it can be prevented in the future. And believe me Imafish, Mr. Lake was no Moron, of which I think the question is still up for debate in your case. I really don’t think you understand the strength of your words as you sit and type at your keyboard. A man is dead. A wife has lost her husband, children have lost their father, a church has lost their frind and pastor. And you can sit and pass judgement that he is a “Moron”. Shame on you.
Brenda-
I like the way you think. I must admit I have not been in this paticular church but have been in several in the Waco area. I have also tied into many of their systems via the master mixer board to record sound for video production. On “most” of the modern sound systems the mic inputs are electrically isolated from the amplifiers via op amp and optical isolation circuits. (for the purpose of noise reduction and isolation) Now that does not mean that this church has a newer system, but the system I think you are refering to would be an outdated older stand alone type of amplifier?
I think the theory that the water was hot, and the mic acted as a ground might be the most valid. If this is not the case, then their PA system is seriously defective because a mic should never have enough current to kill someone.
They’re not sure at this point how directly involved the mike was in the incident. I’m a student at Baylor University, and my understanding from talking to someone who was there that he was not using the mike while in the Baptismal, rather that he slipped while he was getting in and grabbed a mike for balance. I’d appreciate it if we could be a bit more respectful of him. University Baptist Church does have many wireless mikes, I’ve attended in the past. So far they haven’t seen any faults in their audio system.
David-
My thoughts and prayers are with all of you at Baylor. I have not been inside this church, but was wondering if you knew of an underwater light, or if cords were laying across the floor near the baptismal?
Thanks.
This situation doesn’t require “multiple failures”, defective equipment, or anything of the sort… all it needed was for the neutral and hot AC wires to have been swapped at some point. (ANY single point.) This was really common back before wall outlets and the devices that plug into them were polarized. Everybody knew that if the Fridgidaire shocked you, you had it plugged in “backwards”. I have lots of vintage guitar amps, and if you plug them in backwards, the chassis will be tied to the HOT leg of the AC service, and if you touch anything “grounded” through that chassis (guitar, mic, etc) current will try to find a way to ground through your body. I remember seeing SPARKS come off of my lips once when I touched a hot microphone. (I wasn’t standing in water, though.) As previously mentioned, a ground fault interrupt will prevent this; it basically compares the current flowing out of the hot leg with the current flowing into the neutral leg, and if there’s any difference (i.e. leakage to ground anywhere) it shuts down. Very effective. If you wanna add GFI protection to your older equipment, buy an $8 hair dryer and cut off the cord (and unless you want it tripping every 2 seconds, make sure you connect chassis ground to NEUTRAL.)
Hello DC Young & All: Whatever insight I have comes from working with some truly cheap, hazardous, and misused equipment that may be found in small churches or schools. Here, we probably can’t assume that the amplifier (if it was the culprit) was properly grounded or protected and it may well be an old piece of tube equipment out of a closet. There is much to be said for battery-powered equipment around water. I recall one tube amplifier at a Church camp that had no power transformer – only a single selenium rectifier (and filter) to create DC from the line voltage – and a 2-prong power cord. If you plugged the amplifier in with the plug oriented one way, you got a mild shock. Plugging it in the other way gave you a BIG shock. As this sad story tells us, “house current” is nothing to play with.
BTW, an electric guitar amp can have the same defects and would produce a similar injury. And I’m guessing that there are a lot of cheap guitar amps around, perhaps accounting for the higher number of reported deaths.
As you have pointed out, this could not happen in a properly-installed sound system because everything would be connected to a good earth ground and any AC faults would be normal and cause a breaker trip.
re: Electric shocks from guitars and mikes.
Some audio amps have 110V AC polarity reversal switches, which when thrown are supposed to help reduce hum; I believe in the old days of rock n’ roll some of these amps were not very well isolated in their chassis, which caused metal parts on the case to sometimes be connected to the hot side of the AC line (I remember this problem with an old Fender tube amp). Since the shield of the coax cable to the instrument or mike is connected to the amp chassis, this would shock a person who, say, held onto his guitar neck while touching a mike that was hooked to another amp which had its polarity switched the other way. It can also happen by coming in contact with any kind of grounded object.
This is very likely how said rock stars were sent to the Great Stage in the Sky (and possibly the pastor, as well). Newer equipment is *supposedly* better designed to prevent this. For example, my present electric guitar has a ground wire to the metal bridge and strings, with a resistor/capacitor AC isolating filter soldered in-line with it (don’t play standing in a full bathtub, though, and then touch the control knobs if they’re made of metal!).
However, I would say that those who built the baptistry were ignorant of the vital need for GFI breakers in ANY location where there is touchable grounded plumbing or water (damp basements, too).
It was God’s Will.
I guess his God ran out of miracle to save him or just didn’t like the job he was doing.
BTW, what do you call the opposite of a miracle? This looks like one of “those”.
ummm, Sam, the guy wasn’t a priest, he was a minister. (psst, he had a wife and kids, and not Catholic)
first of all, my sympathies to the pastor’s family and parisioners.
On many older AC/DC design radios and amplifiers – one side of the AC line is connected to the chasiss. All that is requied is to reverse the non-polorized plug in the outlet and have the shield of the microphone also connected to the chasiss then anyone connected to the shield and earth ground completes the circuit.
this type of design was common on older vacuum tube designs especially
Mike Cannali,
This is almost exactly what I wrote last night in my Safari and then had no Say it! button! (forced to use Firefox to comment tonight)
Many of the amps had polarity switches so you could reverse the polarity at the power switch if the building was wired incorrectly. Experienced musicians would alway gingerly touch the mic to check for a shock before the music started.
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>On many older AC/DC design radios and amplifiers – one side of the >AC line is connected to the chasiss. All that is requied is to reverse the >non-polorized plug in the outlet and have the shield of the >microphone also connected to the chasiss then anyone connected to >the shield and earth ground completes the circuit.
>this type of design was common on older vacuum tube designs >especially
>Comment by mike cannali — 11/2/2005 @ 9:09 pm >
Another place where you can get a potentially deadly shock is from a car battery. Normally, it takes about 60 volts to break down the skin’s normal insulation. However, if the skin has been soaked in salt water, acid gets on the skin, or one is sweating profusely, 12 volts is more than enough. I’ve gotten a tickle working on boats this way, enough to beware.
I’ve heard that even fresh water in a pool can be conductive with ph imbalance and / or bodily salts. The same is probably true of a baptismal bath.
a little personal experience shared here.
in my church we use “ground-lift” adapters, those that convert three prong plug into two prong and basicly remove the grounding pin. That causes all of the equipment to be grounded through just one plug that is without adapter.
that way there is no 60hz hum in the speakers, but if you were to touch a jack of any cable connected to the system you would “ground” all of the equipment through your own body. I’ve touched the cable not knowingly and i’m tellin thats no pleasant experience. Plus imagine standing in water at the same time???
I’m the sound guy in a church with a similar type baptistry. I wondering if the voltage source was a failure in the pump or the heater that are used to warm up the water, the water becomes “hot” with AC, the fiber glass baptistry isolates the water and the occupant, then touching the mic shell completes the path to ground. Experienced something similar on a water heater with an open element at my Dad’s house years ago. Another theory ……
Very sad, my condolences.
Yes..seems unresolved.
I actually just learned about this in class. I go to a technical school and my professor went over this situation and what happened. This was caused by a few key things going wrong.
A ground loop in the church was inproperly defeated. Therefore making the path of least resistance for electricity no longer into the ground of the AC outlet, but from the mixer, through the sleeves of the mic cable (which are designed to carry signal), through the metal casing of the mic, through the pastors body, into the water, then the drain, then pipes, then the actual earth ground. This could have been prevented if the ground on a power supply was not defeated.