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In the comments section of this question, MacGuyver's distant cousin MacGuffin recommended wrapping the innards of electrical switches and outlets with electrical tape to avoid any accidental shorts.

I think this is a great tip. But the innards of electrical switches and outlets are often not exactly the type of shapes conducive to being wrapped with electrical tape.

What technique is recommend to do this? A photo or two would also be most appreciated.

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    Does youtu.be/mY45ZDdiPn4?t=237 help?
    – MonkeyZeus
    Mar 17 at 19:39
  • @MonkeyZeus Yes! Thank you. That's a great video (assuming he knows what he's talking about!), and much better than what I found. Am I the only one who enjoys the magical sound of electrical tape being fed off the roll? :) Mar 17 at 19:44
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    Note that it's good practice when using a metal box and also inside of a double-gang box regardless of material because you wouldn't want the receptacles' screws to ever touch and arc.
    – MonkeyZeus
    Mar 17 at 19:47
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    @RockPaperLz-MaskitorCasket you're not alone. Check this: mattfife.com/?p=3280
    – P2000
    Mar 18 at 4:25
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    @P2000 And just when I momentarily get concerned that maybe I'm a bit too eccentric, you show me the amazing work of someone who makes me look like a normal lizard. I'm putting that one up on the big screen for sure. Those clear tape rolls sound good, but there's just nothing like electrical tape. I might have to give Johan a call and let him know what he's missing. Mar 18 at 4:52
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There is no need for tape inside a device box except perhaps as a wire colour marker (phase taping, etc). Outlets, switches, device boxes, cable, clamps, breakers - all of these devices have clear and specific installation methods that ensure they perform to the safety standards against which they are tested. Hacks like this do not count themselves among those methods.

If you're tempted to put tape in a device box to stop electricity from going somewhere, it's because there is something else in the box that is done wrong, and tape is never the correct solution.

  • If the side screws are not screwed in, screw them in. It takes ten seconds and costs nothing.

  • If the outlet isn't secure, secure it. It takes ten seconds and costs nothing.

  • If the box or outlet is damaged such that it can't be adequately secured, or is dented, or too narrow such that the side screws risk touching the box or is too small to accommodate the box fill - replace the box. It takes fifteen minutes and costs two dollars.

  • If the wires inside are twisted like haywire, tidy them up. It takes five minutes and costs nothing.

  • If the box needs an extender, add one. It takes five minutes and costs a few dollars.

If the wires or insulation are damaged they must be replaced. Tape is not allowed. If I open a box and see a taped device, the very first thing I do is remove the tape and inspect the job hiding underneath because tape inside a device box does tell you one very important thing - that the person who put it there in the first place didn't even trust their own work. And you shouldn't either.

Tape is a band-aid solution. For applications where you would use it to repair insulation it is not allowed by code anyway. Neither code nor device manufacturers require or even recommend that you to wrap tape on outlets, switches, wire nuts, or any other part of anything inside a device box other than for identifying wires.

3M Super 33 is probably the best electrical tape you can buy, and it comes with a 5-year shelf life. If 3M doesn't give it more than 5 years on the shelf, you can be guaranteed that it won't last that long in service. Tape eventually fails - it is not a long term solution and it is not suitable for permanent installations.

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    @DMoore I invite you to share that example. I have already stated that it is not prohibited by code - this is proving a negative. Code does not prohibit putting a carrot in the box either. It is not part of a professional installation. Tape in the box for any other functional reason (ie: repairing insulation, etc) than marking wires is not allowed. You shouldn't wrap your wire nuts in tape either. This isn't prohibited by code either, but it's dumb and symptomatic of not knowing what you're doing - it can hide other problems so it should be avoided.
    – J...
    Mar 18 at 15:30
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    Sorry, but I agree with the "it doesn't do any harm, and may help" philosophy. As has been said before in these forums, the code is a minimal standard for doing things. There are any number of ways that you can go beyond what the code requires. Wrapping or otherwise covering exposed terminals and copper is one of these things.
    – SteveSh
    Mar 18 at 16:46
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    It would go a long way to change the first line to "You should rarely ever do this." I think we all agree that good craftmanship is more important than taping, but it's also important to remember even perfect craftsmanship doesn't last forever. Mounting screws work loose, kids tug on plugs sideways, etc. Any number of things could make a loose outlet touch the side of a small metal box. In those cases, a little tape does anything from nothing to preventing an arc. Yes, the outlet was already poorly situated by then but you're not around! That said, I do think the situation arises rarely...
    – GManNickG
    Mar 18 at 22:47
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    Obligatory xkcd.
    – gidds
    Mar 18 at 23:48
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    I'm wondering if any of the tape enthusisasts here have ever seen what electrical tape looks like after 10, 20, 30, 40, 50, 60 years. Not pretty, and nothing like when new, and very unlikely to still serve its original purpose. Tape is for amateurs. Professsionals use insulation. Don't be an amateur.
    – user207421
    Mar 19 at 0:07
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If you are going to do it you go 3-4 times around the outlet so it covers the metal and doesn't slip off. Also do not use the cheapo stuff that comes in at $2 for 5 rolls.

enter image description here

This shouldn't be a common thing. I do it only when using smaller metal boxes and the side screws are very close to the edge or touching to prevent arcing. If you are leaving too much copper exposed you need to install your outlets better not add tape.

Addendum: There are only certain uses for doing this method. As mentioned in comments I would do this when installing on very small (some older metal work boxes barely hold an outlet), a GFCI in a smaller box or when adding an extension.

Example is you have a small metal work box and if you do everything right you have 1/8" of play. Fine don't put tape on it. It works fine. Then Big Johnny plugs in his monster surge protector with its big ass 3-prong cord and it barely fits in the outlet. Well couple months later Big Johnny wants to move his electronics and he is a clumsy/strong SOB and he wiggles on this thing hard to unplug it.
Well now the outlet screw has loosened and there is a "live" screw touching the metal box.

Well I am the perfect electrician and the perfect electrician installed it correctly without using tape because if you have tape on an outlet it must not be installed perfectly.

So who was right the "perfect electrician? Or is it all Big Johnny's fault? Or should the "perfect electrician" ask the "perfect handyman" to redo every wall in the house and repaint it to install bigger work boxes?

Or do we just add tape in situations that we see a possible issue with to foreshadow any possible issue?

I have had lots of rentals. I have taped outlets, my units are safe and I have never returned to a house, opened up an outlet and saw tape dangling or charred.

Let's get real here would I rather have brand new wiring and bigger work boxes. Well yes. This is the kind of debate that you have about highway speeds. Why don't we just travel at 30 mph max on the highway. There will be hundreds/thousands less dead a year. However the fact here is the tape could possibly save many people from injury (switched outlets, wrong breaker thrown) vs having no tape.

Again limited use cases but in no way can you convince me that no tape is safer.

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    Its adhesive softens into a goo and lets go over time.
    – isherwood
    Mar 17 at 19:49
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    @isherwood Okay, then I've definitely been buying the cheap stuff all these years. I just thought that's how electrical tape performed. Mar 17 at 19:51
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    Agreeing with @DMoore. You should not have to do this often. Maybe when using box extenders. It is also why we state to have the power off when removing and installing switched/outlets as that's when most shorts wold occur. Once secured, it won't contact the sides.+1
    – JACK
    Mar 17 at 20:40
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    @Jack - bought a house a few years ago... All the outlets had tape around them and the guy did a "neat" job... it wasn't sloppy. All small metal boxes... and he really needed the tape on the outlets.... because.... HE DIDN'T SCREW IN THE DAMN SCREWS HE WASN'T USING. So he had bare screw taped and pressing against a metal box... I screwed in all the screws, removed tape... wow.
    – DMoore
    Mar 18 at 4:29
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    Have you really not gotten the memo that quality is a thing and the performance of cheapie vs higher priced items do in fact differ? Anyway the go-to for electrical tape is 3M Super 33. 3M has particular mastery in the adhesive tape arena. Mar 18 at 9:39
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No tape in permanent installations!

  1. Tape glue. No matter how much reputable and expensive the tape brand is, there is always a possibility for the glue to become either liquid, or dust-like, or electrically conductive over time. Yes, I have seen all these things more than once, including all of them at once.

  2. Cooling. Every conductor heats under load and it is the heat that limits the acceptable load. The easier the heat dissipates, the better. Even if it works now, contacts do deteriorate over time. Better cooling means longer lifespan.

  3. Fire safety. When something goes wrong and some contact goes into runaway heating, every piece of combustible matter counts. Most electrical tapes don't burn well, but one can never be sure.

  4. Humidity. Depending on where you are, humidity may condense where you don't want it. In a lot of places it is an expected feature of the environment and the more closed something is, the more water builds up in liquid form inside.

  5. Dust. Tape glue attracts dust. It may promote arcing.

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  • How would you insulate a bare crimp or split-bolt splice then? (Keep in mind the only UL listed heatshrink out there is heavywall with a hot-melt adhesive lining) Mar 18 at 22:38
  • @ThreePhaseEel the reason it's the only UL listed kind is because it's the safest and longest lasting... it also is usually a 3:1 (vs the cheapo 2:1) so you can get bigger shrink and have more clearance to put it on, and it still shrinks down tight; the hot-melt lining keeps the connection watertight and sealed from ingress/egress of anything else undesirable.
    – Doktor J
    Mar 19 at 0:16
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    @ThreePhaseEel Insulated crimps, shrink tube, or a proper, insulated splice terminal (Polaris, etc). Split bolts with tape should be banished, imo. I do industrial wiring all day and tape is nowhere to be seen. The last guys still taping wires retired about twenty years ago by my reckoning. Tape simply does not last - not even the good stuff.
    – J...
    Mar 19 at 14:38
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Electricians look at tape wrapped around switches, receptacles, and wire nuts as an amateur tell. I agree it's a bad idea around a wire nut, but I am in the minority that feel it's a good idea around device screws.

If someone ever wants to remove the device from an energized box - which there's very, very seldom a good reason to do - who ever takes it out hot will think highly of who ever wrapped that device. You don't have to play a high stakes game of "Operation" with a 277 volt switch.

But there's a much better reason. When you fold up the wires to close up the box, if you're careful, you can keep the bare grounds from touching the terminals and everything will be fine. Except when one of those bare wires doesn't cooperate, and wiggles its way into contact with one of the terminals. It shouldn't happen, but it happens all the time.

If it winds up making contact with the hot terminal, the short will immediately trip the breaker, you'll fix the problem, and life goes on with just a little wasted time and effort.

If it winds up touching a neutral terminal, you could wind up closing up and leaving a ground fault. A GFCI will catch it, but you may have a headache finding it if you did other work at the same time.

If it's just a hair's breadth away from the terminal, it may not create the fault until the switch is switched a few times or cords are plugged a few times, wiggling the device just enough to touch the bare wire. Sometimes it will even create an intermittent problem with an AFCI or GFCI protected circuit and that can waste a TON Of time. When you drive back repeatedly to chase your tail on this problem, whether you're doing it for free under warranty, or doing it for an irate customer paying for you to run in circles, you can hold your head high, you're a pro and you don't wrap your devices.

So I go against the grain on this, I think it's OK to wrap your devices with tape. As mentioned in another answer, don't use junk tape. The only ones I have seen with the necessary stretchy-ness is 3M brand 33 or 88. Apply a little tension when you wrap and these will form nicely around the bumps and etc.

The only problem with tape, besides the disdain of misguided professionals, is the mess the residue makes. Ideal Industries has a new product that solves this, Armourband:

Ideal Armourband

It's a broad flat elastic band that stretches around the device to protect the terminals. So if tape residue is an issue for you, there is an alternative.

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    If someone ever wants to remove the device from an energized box - the first thing they're going to do is remove the tape, get a shock, and realize they should have checked the breaker... and tested to make sure the power was off first. Not convinced.
    – J...
    Mar 19 at 10:24
  • You misunderstand, I am saying there are (admittedly rare) occasions when it's necessary to knowingly work on a live device, they would know it's live, they are not going to accidentally touch a live terminal. That tape will allow them to do what they have to do a little more safely. It's not really controversial, ask an electrician. Mar 20 at 10:16
  • Well, if you're opening a live device and the way you're doing it is not safe without tape or a broccoli band, then it's not safe with it either. Working on live circuits is something that DIY weekend warriors simply should not be doing. Professionals only do it when it's absolutely necessary, and there are ways to do it safely with the right equipment (ie: Class 0 insulating gloves, at least) and procedures.
    – J...
    Mar 20 at 10:24
  • I'd argue that the rest of the argument above is just excusing sloppy workmanship. Ground wires don't have a mind of their own - they stay where the installer puts them. A hair's breadth from the screws is a bad installation. Period. Unless you're installing the device with your eyes closed, one hand tied behind your back, and a box that's two sizes too small then getting wires stowed cleanly should not be a challenge, and anyone who feels otherwise should not be installing electrical equipment in the first place. It's a huge red flag that the installer has no confidence in their own work.
    – J...
    Mar 20 at 10:30
  • @J... I agree with batsplatsterson that ground wires can have a "mind of their own" in spite of your claims. I agree that wrapped outlets is a sign of DIY work, that's because a pro is often more concerned about getting done before the sun goes down than anything else. If the breaker doesn't trip and the little lights on the tester come up all green then they are done, neutral faults to ground are not their concern. A homeowner, the person that has to live with their work, is going to take the time to put on suspenders to go with the belt.
    – MacGuffin
    Mar 21 at 15:42

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