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Green slime out of 115 volt receptical

Green slime out of 115 volt receptical

Green slime out of 115 volt receptical

No I do not smoke crack cocaine and I never have.
The situation is this:

Outdoor hut with an electric heater in it.

Used for an hour a day

The wire feeding the hut was a 16 gauge outdoor cord (no I did not put it on.)

Green liquid comes out of the slots

RE: Green slime out of 115 volt receptical


Well hmmm besides 16AWG being WAY to small to run most any room heater safely I would guess what has happened to be as follows.

Since this was poorly wired, size wise, I would imagine everything else related to this installation is messed up badly too.  If the single major item is wrong (the wire), there is every reason to believe ALL the subtle aspects are messed up too.

The most likely cause is that water has come down the wire from outside because of no drip loop, and no sealing.   Once water gets into an outlet the brass contacts that they are all based on will create a green salt that will get all over inside the outlet.  If it makes it between the two sides of the line it will furiously foam even more green salts.  Add a little more water down the wire and it will come out.  Or plug something in reducing the inside volume and more slime will be pushed out.

This is all bad.

It needs to be fixed!

RE: Green slime out of 115 volt receptical

'frankiee (Marine/Ocean)'...

I wonder if the "Marine/Ocean" industry tag is a clue as to one significant contributing factor (the salty and wet ocean environment)?

A complete rewire, with better sealing, would seem to be in order...

RE: Green slime out of 115 volt receptical


Sounds right
The brass breaking down and the zinc flowing. I think zinc is green??
I got the hut for parts and have since taken it apart.
When I took it apart I noticed the green stuff.
As a matter of fact I have noticed that green stuff coming out of a house outlet before and told the landlord to get an electrician. Electrician did nothing about it. Didnt even pull the cover as far as I know.
I just wanted to know if any one else ever seen this condition.
I have asked many people and none of them ever seen it.
I figured that it was the brass breaking down in the presence of heat and water. Im guessing that zinc is green.

RE: Green slime out of 115 volt receptical

Thanks for the reply
This happened on land and in winter conditions.
I agree that a rewire with proper sealing would be in order if I had not demolished the hut.
It is something that I can be aware of in the future.

RE: Green slime out of 115 volt receptical

Does the green slime come out to feed at night?

It's probably copper salts and will be conductive so take care..

RE: Green slime out of 115 volt receptical

Ahh, the green slime strikes again. Heres another forum discussion of related interest.


Wheels within wheels / In a spiral array
A pattern so grand / And complex
Time after time / We lose sight of the way
Our causes can't see / Their effects.

RE: Green slime out of 115 volt receptical

Naaah naaah you guys got it all wrong.

I got the truth from an engineer at the power company
If your outlets are black the power is from a coal plant
If they are wet the power is from hydro
If they glow in the dark the power plant is a nuke.
So if it is green it must be some environmentally approved source.
He got this from some environmental guy talking to school kids  -- cant believe it.

Seriously the green stuff is copper oxide.  If you have moisture present you really need to fix this - just the moisture can pose a seriouc shock hazard.  The green goo just REALLY shows you got a problem and need to fix it.

Electrical components that stay dry dont get green.

Dan Bentler

RE: Green slime out of 115 volt receptical

I presume he fixed it a month ago..Or the hut has burnt down anyway.

RE: Green slime out of 115 volt receptical

The new outlets on the market out here are clear.
New clear outlets :)

And if little bits are coming out of the socket, you may have this:)

Wheels within wheels / In a spiral array
A pattern so grand / And complex
Time after time / We lose sight of the way
Our causes can't see / Their effects.

RE: Green slime out of 115 volt receptical

These data-over-power-line devices are scary.  These are not twisted pairs, not shielded, no regular impedance.  I can imagine the EM background noise raising considerably if this gets adopted.  Broadcast programs will become more and more difficult to catch.  Who imagined that the power outlets will be able to spit bits in the future, in addition to green slime.

RE: Green slime out of 115 volt receptical

I just found this forum after a search on the green slime. I've seen this stuff twice recently, but it was coming from electrical plugs on two devices: a very old movie projector and a fairly new coffee maker. Both were stored in my basement for about 5 years, and both had the same substance oozing from the plug ends of the power cords.

This is thick, transluscent blue/green goo, and I couldn't find anything that would desolve it (mineral spirits, amonia and soap & water, etc). It looks almost like melted hard candy.

I know what oxidized copper looks like, even mixed with water, and this certainly isn't the same. I was wondering if maybe radon or oil-burning byproducts were reacting chemically with the insulation and/or wire. I still have the coffee maker, and I might take it to a local college chemistry lab to see if they have any thoughts. I'll post the results if/when I get them.

RE: Green slime out of 115 volt receptical

Were these cords exposed to water?
High temperatures >140F?

What exactly are the cords and plugs like? Guess at the materials.

Better yet, take a GOOD high quality picture and post it in here. Mind the size tho!
(FAQ238-1161 explains picture posting)

Maybe we need a chemist to join in here.

I have a PG&E guy standing next to me that is describing the EXACT same thing happening at the function of the clear
plastic sampling tubes and the brass fittings they connect to on gas detectors.  Lots of moisture comes up the tube along with hydrocarbons and brass brass brass... Many corrosion products of brass are green.  Your cords/plugs  have brass contacts, as do outlets, as in the original posters case.


RE: Green slime out of 115 volt receptical

As has been noted many corrosion products of copper are green. If the corrosion is a slime I would suspect that there are degrading polymers present that are supplying the source of corrosion. Old rubber will turn to goo and can contain sulfur and chlorides. Almost all polymers used for electrical insulation contain flame retardants which are often chlorinated. PVC is inherently flame retardant because of its chlorine content. If the socket got hot due to contact resistance and high current the polymer insulation of the wire probably fried and released hydrochloric acid and other corrosive materials. Flexible PVC also contains a lot of plasticizer which is basically an oil and this is probably part of your slime.

RE: Green slime out of 115 volt receptical

That's the info we were looking for Compositepro.. Thanks very much.

Wow, quite the chemical morass in those cheap plugs......

RE: Green slime out of 115 volt receptical


Thanks for the replys.
I have taken apart the hut for use in parts.
I saved the outlet so I could show people.
I just came back from the ship since Sept. and I have found a similar example on board ship.
Thank you for explaining the cause.
A lot of people don't even believe in the green slime.
I sent a picture but even the picture does not show how runny it was during the summer.
Thanks again.

RE: Green slime out of 115 volt receptical

Thanks frankiee.. Finally put a face on it...
And it is UHHGGGGLY.

RE: Green slime out of 115 volt receptical

Doesn't look like an appropriate installation at all. The presence of the white salt crystals indicates an area that is sometimes wet with seawater. That stuff is a tad corrosive.

RE: Green slime out of 115 volt receptical

Please find below a couple of paragraphs from a publication produced (by the NICEIC) for electricians in the UK - it may be the problem you're experiencing:

*****************NICEIC Excerpt Starts**********
Green goo is a phenomena sometimes encountered in electrical installations constructed in the late 1960s.

Unsightly green slime can occur in switch and socket-outlet boxes.   It is understood that this phenomenon is most prevalent where pvc cables manufactured between 1965 and 1971 have been used.
The green slime, or green goo, is degraded di-isoctyl phthalate and is considered to result from a chemical reaction between the plasticiser of the insulation and the copper conductor in the pvc cable.   Between 1965 and 1971 the temperature performance of pvc was uprated by the inclusion of an anti-oxidant into the pvc compound. An unappreciated side effect was that the anti-oxidant encouraged production of the exudate.
There is evidence to suggest that high ambient temperatures accelerate the process. The exudate is of low flammability and low toxicity. Although unsightly, it does not reduce the electrical integrity of the conductor or the insulation. However, the exudate may have detrimental effects on both accessories (in appearance and functionality terms) and their surrounding decorative finishes.

*****************NICEIC Excerpt Ends**********

Hope this helps,


RE: Green slime out of 115 volt receptical

Thanks briand2! I think that pretty much drives a wooden stake into its heart.

RE: Green slime out of 115 volt receptical

Just to clarify if it is corrosion product of copper. Take a small sample of the slime, putting it into a jar.  To the jar add a 20 to 30 ml of household ammonia. Cap the jar and shake. If the liquid turn a royal blue then copper ions are present.

Vita sine litteris mors est.

RE: Green slime out of 115 volt receptical

Yep, that's the stuff alright. Strange thing is it never appeared until I stored the two items in my basement. Would radon gas (5-6 ppm measured) or hydrocarbons from my oil-fired boiler cause a chemical reaction with the PVC? That big puff of smoke whenever the burner kicks on probably isn't a good thing...

RE: Green slime out of 115 volt receptical

The green corrosion sometimes seen on copper is called Verdigris.

Here is a link ->

Also interesting to note; this is why it was very important to keep copper cookware tinned in a Victorian kitchen. It's poisonous.

RE: Green slime out of 115 volt receptical

I thought Verdigris was associated with leather in contact with  brass/copper.  Interesting.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

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