By Chuck Woodbury
EDITOR
Please answer our poll below: Have you ever been shocked by touching an RV? (Voting is closed.)
(UPDATE, MAY 9, 2021) — I wrote this article seven years ago in response to the death of a 3-year-old boy, who was electrocuted by simply touching his family’s Airstream trailer. The trailer was experiencing what is known as a “hot skin” condition. It can happen to any of us, and does, in fact, happen much too often (most often the shock does not kill). I urge you to read this story. Being aware of what causes this potentially lethal condition could save your life or the life of someone you love. Here is my story, slightly edited, from three years ago.
We reported earlier this month about the death of 3-year-old Landyn Gerald Keener, who was electrocuted when he touched his family’s Airstream trailer in Amboy, Ill., when it was experiencing a “hot skin” condition. After hearing the news, our technical editor [at the time] Chris Dougherty interviewed electrical engineer Mike Sokol about how such a tragedy could occur and how other RVers can avoid becoming a victim. Watch that interview on our RV Travel Channel.
Here’s a story by Chris about this incident.
The fact is, a hot skin condition can occur on any RV, new or old. In a nutshell, it’s caused when an RV is plugged into an improperly wired electric plug or cord. In most cases, the only harm that will come to touching an affected RV is receiving a mild shock. But under certain circumstances the shock can be deadly. Here is a news story about the accident that took the life of young Landyn.
Our contributor and RV electric expert Mike Sokol received the following letter after my editorial appeared:
I came across your tutorial on “hot skin” conditions at RVtravel.com. At first I discounted the idea that this could be a frequent enough occurrence to worry about, but the kid who got electrocuted really bothered me. So, I went and bought the Fluke tester to see if the extension cord I was using out of my garage was a problem. Sure enough, when I plugged the RV in as I usually do it came out with a hot skin condition. I was quite surprised, but all the red flags were there in retrospect. And here I was letting my kid play in the unit while it was plugged in at home, and I was going in and out, all of us oblivious to the potential danger.
Here is a scenario of what I actually experienced. And it was of my own making. I’m also both trained, and experienced in both Household, as well as automotive wiring systems and installation. Though even after all these years, I still don’t know everything, and will be the first to admit it. This is one of those times I didn’t know everything, but thought I did. When I was building my little home-built teardrop trailer a couple of years ago, I ended up getting a mild tingling electrical shock by the hot skin condition. Here is what happened. During the process of building the rear galley counter top, I wanted a metal counter-top, with a metal back-splash for my wife to use, as it would be both, waterproof as well as look nice, and also be easy to clean up if water from the sink, or something else was spilled upon it without it ruining the wooden plywood base that was underneath it. I wanted both 120 volt AC, and 12 volt DC electrical outlets mounted upon the back-splash above the counter-top. Due to the thickness of the bulkhead wall between the galley and sleeping compartment I used what is called “2X2’s” (which are actually only 1-1/1/2 X 1-1/2 inches thick). That left no room for a flush mounted wall receptacle box without cutting out the interior wall of the sleeping compartment, or the electrical receptacle sticking out past the back-splash which my wife nor I wanted as it would not look factory built nice. So I just cut out the rectangular hole in both the bulkhead wall plywood, and the metal back-splash, and mounted the receptacles for both the 12 volt DC and the 120 volt AC systems. Now here’s where the Hot Skin Condition problem lies in wait, like a deadly venomous spider in a web waiting for its victim for the unknowing. (1) Generally the 12 volt DC automotive system uses a one wire (hot lead), system with the return wire (ground), being the vehicle’s metal frame. (2) The 120 volt AC house wiring system has the (black), hot lead separate, but also has the (white), wire return and the (green), ground wire tied together within the outlet receptacle and its mounting screw brackets. So, I wired the hot lead (Black) for the 12 volt DC and used the frame for the return as any (older), automotive system uses. – NOTE: I want the 12 volt system to have a household outlet receptacle to be used (Painted red, and labeled as such, that way it would not be mistaken for a 120 volt AC outlet), as a coffee pot receptacle, as of yet no problem. – I also wired the black lead and the white wires as appropriate for the 120 volt AC house system, this is as normal for both systems. No problem so far. Both systems are properly wired. Oh Wait, I get the bright idea to save upon the cost of additional wire, and decide to use the frame of the teardrop as a ground for both systems. So I tie the (green), ground wire of the 120 volt AC household system to the frame of the teardrop trailer, that way the whole system is grounded as a unit. Uh-Oh, the deadly venomous spider now has just completed his web, and is awaiting his first victim. Yes, outwardly, as normal, everything was fine. No smoke signals, blown fuses, or circuit breakers signaling any shorts. WOW ! Fantastic ! However, every time I was kneeling upon the ground while trying to install the sink, and while touching the metal counter top with my arms I would get quite a tingling electrical shock. Needless to say, I would very hastily remove my arms from the counter-top. Not a good feeling. At first, I chalked it up to a simple static electricity shock. But it occurred each time I started to do the same thing again. It took me a while (by trial and error), to figure out what was occurring. I finally figured out that you cannot hook both the (green), ground of the 120 volt AC system to the frame of the trailer as a ground for both systems. Because the 120 AC system’s ground provides an easy pathway for current to run due to the alternating back and forth, both ways of the electrical current. You’ve got to totally isolate the 120 volt AC system (including the ground), from the 12 volt DC system, as well as the frame, otherwise it creates a dangerous Hot Skin condition. Like I said, and will be the first to admit it, even after all these years of working with both electrical systems, I still don’t know everything. None of us do. Well, folks, two things. – I learned something the hard way, and will always remember it, – and – Two, I hope this helps somebody else to be wiser than I was, and not do the same thing and later learn the hard way, just as I did. – Cheers Everyone, and have a nice day. – P.S. I know I’m probably going to get a lot of negative feedback for my stupidity but, I will accept it in humble grace, and I humbly apologize for my stupidity. – I also hope this is posted for others to learn from my mistakes.
Back in my early days of R V travels. I bought a converted mail truck that would shock me every time I opened the door. My fix was to put a large rubber mat at the front door. This worked well until I opened the door in the rain one day. I could not find the problem so I sold it before it killed me.
Hope someone fixed it.
I get emails similar to this all the time. Finding and fixing hot-skin conditions should be really simple. But because electricity is so poorly understood by the public as well as many RV technicians, a lot of potentially dangerous situations go uncorrected.
The most shocking thing about most rv’s is how shoddily they are built.
This condition happened to me in 1980 at a campground in San Felipe ,MX. As I recall,the receptacle had onLy 2 slots and no ground wire slot.My pigtail had the 3 prongs so I put on a 2 prong adapter and filed down the larger prong to fit the receptacle on the pedestal.
Result was hot skin on the trailer. A fellow camper told me to reverse the plug and the problem was solved.
Obviously the wiring on the pedestal was faulty. Back then there were many places with bad wiring as I observed a man sawing ironwood in Keno Bay. Evidently the switch had gone bad and his solution was to cut one of the wires and form a hook on each end. To start the saw he hooked the two wires together and unhooked them to stop. Very unsafe but did the job of a switch!
Never shocked in 25 years of RVing.
While it’s true that a NCVT can’t detect DC voltages, there are typically no direct current power sources available at pedestals or home outlets to power an RV. The DC voltage you may be talking about is probably from solar panels on the RV itself. Those panels are generally 12 or 24 volts DC, which is far too low to cause a shock hazard. If that’s the case, it’s a closed system on the RV which is similar to an on-board generator, so no ground rod is required. However, if you’re running a high-voltage solar cell bank on a separate structure and feeding it to the RV somehow, then that system itself should be earth grounded.
We should also be aware that testers like the Fluke are measuring ALTERNATING CURRENT being radiated from the voltage source (A/C power). The sensor design is unable to detect a DIRECT CURRENT power source. Fortunately for most RVers, hopefully a moderate number of panels in series, or a bank of batteries would not be fatal if miswired or damaged. For those looking for an extra measure of protection, consider using a ground stake (metallic tent peg, etc) that is driven into the ground, with a wire between the stake and a metallic structure on your RV body or chassis.