Zapped again! Static electricity.

[zeeprogrammer]

I just knew putting vinyl down for my floor was going to be an issue. But it is what it is.
For the last few days, as I come up to my machine, I get zapped.
It's more surprising than hurtful but I run the chance of throwing my back out if I get startled.
I also worry about the machines.
In my old job...we did a lot of ESD testing. Products could get toasted, reset, turned off, or start running motors.
I have no idea how well these machines are protected against ESD.

Do any of you have this problem? What can be done to alleviate it?
The usual thing is to touch something to ground myself but I often forget.
I know my shoes are a big part of the problem. Rubber or plastic soled...not good.
Would leather solve this?
Some kind of pad in the front of the machine and grounded?

I wish I could go barefoot but I am blessed with baby feet (as in soft...smell is something way different) and walking on swarf or dropping things on my beautiful tootsies makes it out of the question.

[MJM460]

Let me guess, Zee.  It is getting cold outside, you have the electric heating bringing you up to a nice comfortable temperature, your clothing is genuine pure wild Orlon, a totally non conductive vinyl floor and when you walk up to your nicely plugged in machine with a good solid earth pin connected to ground, you get zapped.

No surprise there at all.  Your humidity is hovering around less than 10%, and your clothing is a perfectly Van de Graph generator, primed to work on your every movement.

Try a humidifier to bring the humidity to a more comfortable level and cotton work clothes.  Wool also works well but I am not sure of it is so readily available there.  I would expect leather would also work if you have a comfortable garment.  But I believe you need the humidity so there is a conductive path for the inevitable charge.

I never saw such large sparks until I worked in Canada under those conditions.  With -20 F outside the the electric heating created humidity levels lower than I ever saw in the desert.  Cotton clothing is compulsory in the oil industry, here anyway, I believe as much as anything to minimise sparking.

If you have an induction motor powered machine, I would think it would not be sensitive to ESD.  And while a variable speed machine has the electronic controls, it should be very solidly earthed along with the power supply, so I suspect they are also not affected by ESD.  But we have a few Electrical engineers on the forum.  Maybe one of them could comment.

By the way, welcome to retirement, you will soon wonder how you fitted in work.

MJM460

[Noitoen]

There are some strap on grounding attachments for regular shoes.

[Admiral_dk]

Most electronics today are very well protected against ESD - both at the component level and at system level. As a matter of fact - all electronic components rated for vehicles are tested and guarantied to withstand horrendous ESD discharges and the same goes for Health equipment - commercial components are rated lower @ 5-15KV.

So I would say that all quality brands are well protected - but I can agree on it being a real problem back in 1970-1990 in the electronic business.

[Roger B]

Carl, the problem is obvious, you are not doing enough machining!!! When the floor and your shoes are completely embedded with swarf they will become conductive and the problem will go away 

On a more serious note the safety shoes I wear in the work shop are anti-static, something like this may help. Otherwise increase the humidity, but not too much. You don't want to exchange the shock of electricity for the shock of rusting machines 

You could also paint the floor with something like this:

http://na.henkel-adhesives.com/product-search-1554.htm?nodeid=8798046388225

to make the surface more conductive.

[zeeprogrammer]

Thanks all.
I can try increasing the humidity. It's part of the A/C system.
I'll also try some other shoes. I had worn two different pairs of shoes yesterday and it was particularly bad with one of them.

Carl, the problem is obvious, you are not doing enough machining!!! When the floor and your shoes are completely embedded with swarf they will become conductive and the problem will go away 

 

[Noitoen]

Try something like this

[mklotz]

I think you need to put one end of a length of chain under the waistband of your tutu and let the other end drag on the ground. 

Might not solve the static shock problem but the video would instantly go viral and you could make a fortune selling advertising space.

[crueby]

I think you need to put one end of a length of chain under the waistband of your tutu and let the other end drag on the ground. 

Might not solve the static shock problem but the video would instantly go viral and you could make a fortune selling advertising space.

 

[ShopShoe]

There are Anti-Static sprays that help: Google "Anti-Static Spray"

There are also anti-static ionizer devices" Google "Anti-Staic Air Ionizer"

These do help some. Raising the humidity is really the blanket prescription.

(BTW: I really good humidity-measuring device is very helpful.)

--ShopShoe

[zeeprogrammer]

I think you need to put one end of a length of chain under the waistband of your tutu and let the other end drag on the ground. 
Might not solve the static shock problem but the video would instantly go viral and you could make a fortune selling advertising space.

No matter what thread...I cannot escape. 

Thanks again everyone.

I've got a humidity measuring device in the basement. I'll bring it up and see what's what.

[crueby]

I think you need to put one end of a length of chain under the waistband of your tutu and let the other end drag on the ground. 
Might not solve the static shock problem but the video would instantly go viral and you could make a fortune selling advertising space.

No matter what thread...I cannot escape. 

Thanks again everyone.

I've got a humidity measuring device in the basement. I'll bring it up and see what's what.

Nope. No escape. We have a tracker collar on you...   


Have you tried turning off your Tesla coil in the garage?

[mklotz]

I think you need to put one end of a length of chain under the waistband of your tutu and let the other end drag on the ground. 
Might not solve the static shock problem but the video would instantly go viral and you could make a fortune selling advertising space.

No matter what thread...I cannot escape.

You're lucky I wrote "under the waistband of your tutu".  What I wrote originally and then erased was much more graphic.

[michaelr]

Grounding the floor may be the way to go.

https://www.staticworx.com/articles/Best_Way_Ground_ESD_Flooring.php

Mike.

[zeeprogrammer]

Thanks Mike! That's certainly worth looking into.

A worthwhile suggestion...unlike other contributors here. 

Now they'll pop in again and argue their suggestions do have value. 

Well okay...a good laugh is always valuable.

[Stuart]

Zee
You can test that idea out , now listen very carefully, get a rewireable plug with a earth pin (ground on your side of the pond) now get a single strand of insulated earth wire and wire only that wire into the plug on the earth pin bare the other end place on the floor put a lump of metal on top of it plug in but don’t switch on just to be doubly safe

Take care we don’t want you to look like the cartoon skeleton getting a belt

Stuart

[MJM460]

OK, Zee, I am a bit slow on responding to my cue but possibly better late than never.

I am sorry my attempt to be lighthearted obscured the basic message.  Yes, my kids also say I have a strange sense of humour.  Or perhaps you missed my answer.

So down to a bit of root cause analysis.  Getting zapped by static?  So where does the static come from?  Remember that bit of ebony rubbed on the pierce of fur in junior science?  The friction between really non conductive materials displaces some electrons or something like that, and very high voltages are built up.  Your nylon/ rayon/ polyester clothing is a pretty reasonable non conductor, especially if there is not much humidity.  I am not 100% sure on the polyester, may depend on the actual composition, but nylon and rayon definitely.

Earth straps and the like will connect you to earth, but never seem totally the answer.  Why?  Well, how does the charge get from where it is generated to the strap?  They solve the non conducting floor issue, so sometimes help, but not the clothing.

Cotton clothing seems to work.  Not sure if the cotton is inherently slightly conducting.  It was used for insulation in the early days, so if so, it would have been leaky insulation.  More likely, it is hygroscopic and wicks any moisture from the air or sweat, to become conducting.  And in a conductive fabric, no generation of static charge.  Even a megohm is conductive in this context.

The oil industry, at least the places where I worked, which covers a good range as we were design contractors, insisted on pure cotton, though I am not sure why a good cotton/polyester mix would not work, and is probably more available.  It's possibly about removing doubt about identifying the actual synthetic in a garment.

The problem also occurs in liquids, aviation gasoline is a real bad actor.  Friction in filters and just from velocity shear builds up high voltages that can spark inside tanks.  The fluid is non conductive, but also does not dissolve water, so a bit of water seems to disperse into tiny droplets which I have heard make the problem worse.  Everything is well earthed in a hydrocarbon processing plant, but sparks still occur with out additional precautions, as there is no conductive path from the middle of a large tank to the earthed metal wall.

I had a quick look in my wardrobe, and I have pure cotton, some cotton polyester mix and even some pure nylon, though it comes treated with fly repellant, perhaps that makes it conductive.  In addition my workshop is basically only uncontrolled solar heating, the type that doesn't work well in winter.  No zapping problem, though we never have really low humidity.  Don't get zapped in the home.  Occasionally in very dry weather, zapped when I get into or out of the car which seems to build up a charge sometimes, no doubt the tyres are non conductive.  They are no longer full of carbon.

Of course if you already have cotton clothing and a humidifier, all this is not helping you much, but it is a known potential cause to consider.  And, as I said before, I never saw such sparks on removing a shirt until I was living in Canada with electric heating!  The electric heating results in really low humidity when the fresh air outside is -20.  So not totally irrelevant.  I am sorry if it was not helpful.

MJM460

[zeeprogrammer]

@MJM460 I don't see anything you wrote that needs apologizing for. Your post was helpful.
Controlling the humidity will certainly improve things a lot.

At work we had to deal with this issue quite a bit. The products used belts and rubber wheels and transporting banknotes would cause spikes in the recognition system.
Most noticeably in dry cold weather. We built a 'dry box' where we reduced humidity in order to test changes made to the product.

[Ian S C]

In the late 60s, early 70s when I was doing my Nursing training we soon found that making beds could be quite exciting, if you flicked the sheets off a bed you could draw a 2" spark off the bed frame to the nearest part of your body(usually the leg). In Operating Theaters, and other areas with high use of inflamable gas and oxygen, conductive Lino is used on the floor to prevent the build up of static electricity.
I know that some people(my Dad was one) get shocks off their cars, but the tires should be conductive, there is quite a large amount of carbon added to the rubber mix in the form of lamp black.
Ian S C

[MJM460]

Thanks, Zee,

The main thing is that we all hope you are able to get the issue sorted.  Those zaps are not fun.

MJM460