The case of the shocking shower
“… and I got shocked when I turned off the water,” said Luke, as I tucked him in for the night. “Right,” I thought, “how can you get a shock from the water pipes?” Still, I had felt a little twinge earlier in the evening when I had turned on or off the tap in the bathroom sink. I thought it was just one of those little shock-like stabs we get now and then from whatever cause. Still, maybe I’d better check.
We were on vacation at the SIM retreat center in Miango, not far from Jos. It was Monday night, our first night of a six day stay, and we had already changed rooms once because the fan didn’t work in the first one (see how spoiled we are now?). I had to travel to Abuja the next day to give a presentation at a training session for doctors working children infected by HIV, so Barb and Luke would be alone.
In the US, we used to take electrical safety for granted—not ignoring dangers, but knowing that if we followed the rules we would be safe. In Nigeria, all bets are off. One high-priced electrician connected some of our home’s outlets with the hot and ground reversed: touch the outlet screw and get a shock. A hospital electrician reversed the neutral and hot for a whole section of the compound, causing a lot of damage including our hot water heater wires burning. A contractor, repairing wiring in one of the wards, used cheap telephone wire or something similar rather than the proper gauge wire, causing an electrical fire in the ceiling. I won’t go on, but really, electrical safety is a nightmare in Nigeria.
I went into the bathroom and gingerly tapped the tap, this time without my shoes on. Yes, there was a distinct though mild shock. Ah, well, I thought, probably one of those little shocks from some floating ground or something. Pretty strange, though, how would there be an electrical potential between the floor and the cold water pipe? At that point, a prudent course would have been to stay away from the whole mess until I could get a test meter or something, but I curiously (and quickly) dipped my finger into Luke’s now-tepid bathwater. Ouch! This time it was a real shock for sure. The rest of the evening we were careful not to touch the water or the pipes.
Grounding rod and connecting wire
Click on photo for larger view
The next day, I borrowed a voltmeter from dentist Steve Porter and verified that there was indeed high voltage on the pipes. Steve had mentioned that a cracked water heater element could cause this, but turning off the heater didn’t help. Checking the house’s grounding system showed half the problem: a grounding rod was there, all right, but the wire was just loosely wrapped around the corroded rod like a bad joke. So the house’s wiring was a setup for disaster, but still, why was it the pipes that were “hot?”
The second piece of the puzzle was that the plumbing inside the house was metal, but joined to PVC plastic pipe at the outside wall. This meant that the metal pipes themselves were not grounded.
Finally the maintenance crew arrived, shortly before I had to leave for Abuja, and traced the problem. It only happened when something was plugged into a certain outlet. Apparently, the outlet was faulty so that when something was plugged in, the hot wire was pushed over to touch the ground. Somewhere the housing ground wire must be connected to a water pipe. The result was that when the outlet went bad, the whole plumbing system effectively became part of the hot side of the electrical wiring! Since I was reading an Agatha Christie mystery at the time, I wondered if couldn’t form the plot of a murder mystery.
The immediate problem was solved by replacing the offending outlet. By the time we left, however, the real problem of the useless grounding system had not been fixed. Long term problems are not something that get much attention here …
October 21st, 2007 at 7:05 pm
Hey Mike. I know when we had to set up the gen for KA it was the biggest nightmare and I was just involved in the money part. When I lived in the de la Haye house, I was shocked any time I tried to cook something without shoes on. Now if you wanted to use the stove and the oven, well that was just a death sentence. I think eventually the ground wire was removed???!!! The shocking wasn’t so bad after that.
When I moved to Jos, I loved my gas cooker.
October 21st, 2007 at 7:12 pm
Oh and the water pipes shocked too. I had to have shoes on to shower and turn on the sinks. So when you started the story it made me think of the de la Haye house. Luke does tell the truth even if it sounds crazy.
October 23rd, 2007 at 2:12 am
My son sent a link to your blog to me with the shocking shower title. He was in Jos in March, 2006, with a group from a local church in Rockwall, Tx. That must have been how he happened to find your story as he keeps up with news about Jos. As a master electrician in Dallas, Texas, I believe this information can aid in making you electrically safe.
Correcting the grounded conductor and system ground wiring will prevent such a shocking problem again with anything that makes incidental contact with a live source of electricity, unless the connections become loose and/or corroded. It should make any future “short” trip a breaker or blow a fuse before someone is shocked. It will also make the ground rod (which should be at least 1/2″ copper coated steel and driven 6′ into the ground) and connections to the ground rod to the standards set by the National Electric Code which is used in the USA and many other countries as a minimum standard for electrical safety
The loose ground can be corrected with an acorn ground rod clamp or a pipe grounding clamp. The metal to PVC connection should be bypassed with a grounding electrode conductor directly from the metal pipe with a pipe ground clamp to the ground rod. Perhaps the ground rod can be relocated to a place nearer the metal pipe to facilitate the connection. Another ground rod could be driven close to the metal pipe if the first one cannot be removed. If two ground rods are used they should be interconnected with at least # 4 copper wire AWG if it is exposed (not enclosed in a wall or conduit) or the connection to the ground rod should be at least # 6 copper AWG if it is “protected from physical damage.”
My son’s friends in Jos may have connections with local electrical suppliers who could get adequate ground rods, a ground rod clamp, a pipe ground clamp, and #4 or # 6 wire. SIM probably has similar connections.
Feel free to reply to me if you cannot get the supplies you need there. I am sure they could be shipped to you if needed.
October 23rd, 2007 at 7:19 am
Thanks, Fred. As in many different issues here, the problems are not in the knowledge as much as in the whole attitude and outlook on life. Remember “hakuna matata” — “no worries” — from The Lion King? It really does describe a lot of the way of life here.
It would be great to have you visit Jos sometime and do some inspections, work, consultation and so on for the missions here and the hospital. Let me or your son know if you’re interested!
October 24th, 2007 at 7:55 am
A murder mystery plot….I think you might have something here! We had an electrician in Tera who was supposed to be fixing a light. He touched two live wires to see if they were alive. They were and blew the fuse. So we put in another fuse and he immediately did the same thing! The problem was….that was our last fuse. He looked all through the market in Tera and couldn’t find our kind of fuse. No way were we making a three hour trip to Niamey just for a fuse. So we had to use candles and lanterns in the living room for a month until we went to Niamey. When we went to buy a fuse, we were sure to buy an entire box of them!
October 24th, 2007 at 8:19 am
A whole month without light … I wonder whether the lanterns and candles were safer than the risk of going without the fuse. Was there no one to send on a motorbike or camel to Niamey, a regular merchant or something? Sounds pretty isolated.
October 24th, 2007 at 8:07 pm
Do you still have the series of crazy electrical wiring photos that used to be on your blog? I could not find them last time I looked.
FYI-Also as I know you have wide and varied interest. Have you looked through the Doctors Without Borders blogs yet? They are very interesting.
http://www.msf.ca/blogs/
October 24th, 2007 at 8:30 pm
Those “crazy electrical wiring” photos are on Flickr in my “Wires of Nigeria” set.