Static electricity issues

[Sticks]

At work we sometimes can get static electric shocks off of metal cupboards, the lift button, the open door button, door handles.

When we complained about this, as we are in a newish building, we were told that the carpets had some anti-static coating and it was all due to the clothes we were wearing.

How would a carpet anti static coating work? Are they right that it is all the fault of our clothes?

Also when contemplating the shocks off of the filing cabinets, they are free standing on the floor and I can not see any connection to an Earth mains, so why do I still get shocks off of them.

[Huevos Grandes]

It is possible to buy carpets anti-static coating. It's just a chemical goo that they dump onto the fibers at the production plant- most commercially sold carpet is loaded with chemicals, and account for the thick black smoke when your house is on fire.

As for the clothing causing the static build-up- it's possible to slink around in your clothes enough to build up some charge, but it's very suspicious that many individuals in your office (with different wash & drying cycles for their clothing) are experiencing this. Perhaps the anti-static coating on the carpet isn't working, or else something else is generating the static electricity. And you'll ground yourself touching almost anything attached to the floor/Earth: a filing cabinet, another person, a plant, etc.

[papageno]

At work we sometimes can get static electric shocks off of metal cupboards, the lift button, the open door button, door handles.

When we complained about this, as we are in a newish building, we were told that the carpets had some anti-static coating and it was all due to the clothes we were wearing.

It is possible, especially if you have insulating shoes (like, with rubber shoals).
How many people are having these problems?
If it is wide-spread, and the people do not wear all the same type of clothes (like uniforms or following some other dress-code), then I would say the problem is with the building.

How would a carpet anti static coating work?

If I remember correctly, it should be a slightly conductive coating so that charges do not accumulate easily and then flow easily to earth without a real discharge.

Are they right that it is all the fault of our clothes?

If you have a wide range of clothing, I would say that it is not your fault.

Also when contemplating the shocks off of the filing cabinets, they are free standing on the floor and I can not see any connection to an Earth mains, so why do I still get shocks off of them.

Maybe there is something in the walls, out of sight.
It is hard to tell without actually being in that building.

If you feel adventurous, you could go around with a voltmeter, and measure the voltages between various points (cabinets, doors...) and the ground.

[NEOWatcher]

Does something need to be grounded, or does it just need the capacity to absorb the charge (or balance the charge between your body and the object)?

Humidity? The drier the air, the worse the static. (I've heard that, but can't explain it)

[swansont]

Even if a piece of metal isn't grounded you can still get a shock — if you are charged and it isn't, you are at a different potential, and the current will flow.

[Swift]

Does something need to be grounded, or does it just need the capacity to absorb the charge (or balance the charge between your body and the object)?

Humidity? The drier the air, the worse the static. (I've heard that, but can't explain it)

I always assumed it was because dry air had a lower conductivity, but according to this article, that's not it

It is well known that static-electric problems seldom occur in environments with high relative air humidity, say, greater than 50–60%. This fact has sometimes been erroneously interpreted to mean that humid air has higher conductivity than dry air. However, if anything, humid air is less conductive, because the mobility of small air ions decreases slightly with increasing humidity. The effect of increased air humidity is to increase the thickness of the moisture layer on or in all surfaces, and this layer contains electrolytic ions that provide neutralizing charges.

The article contains lots of info on static, anti-static controls, etc.

[Nicolas]

If you think we have issues with static electricity:

I just freed a fly who was upside down with it's wings stuck onto a plastic protective sleeve for record sleeves.

[Enzp]

We have static problems from time to time. it is the carpet. Walk around in the same clothes in an area of tiled or concrete floors - the entry foyer or the parking lot for example - do you get shocks there?

Commercial carpet cleaners commonly will add anti-static to their cleaning products if requested. Count on it costing a bit more though. But what we always did was to do it ourselves. Get a spray bottle, and mix a dilute solution of some sort of home laundry "fabric softener". These products advertise they prevent "static cling" in your clothing. Lightly spray this stuff on the carpet in traffic areas. Not only will it reduce shocks, but the carpet will smell April Fresh.

[Sticks]

It looks like the people who look after the building are attempting to address the issue, however in one of the screeds given they said this

A a static shock is a kinetic energy we are limited as to what we can do about the shocks individuals receive. The kinetic energy is generated by a number of factors such as certain materials in clothing and footwear, dryer air and friction.

I never thought of static electricity as kinetic energy, I thought that was the energy of a body in motion given by E= 0.5MV².

One of our engineers says that is correct as there are only two types of energy, potential and kinetic, and a discharge is kinetic due to moving electrons.

Is this right?

It just did not seem right when I first read it.

[swansont]

One of our engineers says that is correct as there are only two types of energy, potential and kinetic, and a discharge is kinetic due to moving electrons.

Is this right?

It just did not seem right when I first read it.

It's not incorrect. A charge q accelerated through a potential difference V will acquire a kinetic energy of qV. The potential energy beforehand is qV.

This view requires you to e.g. think of mass as potential energy, which IMO requires a little shoehorning of concepts, but I don't think there's an inherent conceptual error in the viewpoint. (A little like saying there are two types of people: those who divide people into two types, and those who don't.)

[snarkophilus]

One of our engineers says that is correct as there are only two types of energy, potential and kinetic, and a discharge is kinetic due to moving electrons.

Is this right?

It's a really wishy-washy way of getting out of answering the question. The actual shock may be due to the motion of electrons, but the cause of the shock is the storage of electrical potential in different objects. Really, the whole potential/kinetic thing has nothing to do with your problem, and the excuse they gave you is rather silly. If they can't prevent problems due to kinetic energy, then there's no point in wearing hard hats at construction sites, now is there?

The problem is that charges are being generated and stored in different surfaces, and when those surfaces come in contact with each other, there's an electrical discharge. A nice way to avoid getting shocked yourself is to touch a piece of your clothing to the file cabinets/door frames/whatever before you actually touch them.

The problem's usually worse in the winter, and usually there's little you can do about it other than frequently touching different things (so that your body never has the chance to build up a large charge). I haven't tried different detergents, but I assume that some are better than others for preventing static build-up. If you're in a workplace where static is a concern, like a chemical plant or a computer place, then your employer needs to do something about it, but if it's just a little unpleasantness when you touch the door knob, I think you're out of luck.

[enginelessjohn]

I've done some work in electronics factories in cold dry conditions, and despite all the ESD precautions (painted floors, conductive shoes and coats, wrist strips) you still need to be a little careful.

The easiest way of avoiding ESD shocks is to carry around one of the dark plastic bags that computer components come in, and it will have a symbol on it like this...

http://www.esda.org/images/esdsym21.GIF

These bags are slightly conductive, so any charge flows slowly to the lower potential any stops any sparking. Before touching anything pop your hand in the bag and touch something at ground potential. Taps (faucets for our 'Mericans) are good, as is the metal case of anything that is plugged into the mains.

Cheers
John

[Sticks]

where can you get those bags?

[enginelessjohn]

where can you get those bags?

In any IT department. Failing that, ask nicely at PC world, or somewhere like that.

Cheers
John

[JohnOAS]

I've done some work in electronics factories in cold dry conditions, and despite all the ESD precautions (painted floors, conductive shoes and coats, wrist strips) you still need to be a little careful.

The easiest way of avoiding ESD shocks is to carry around one of the dark plastic bags that computer components come in, and it will have a symbol on it like this...

http://www.esda.org/images/esdsym21.GIF

As suggested by (another) John, if you have any sort of electrical gear on your desk/bench/work area, a quick solution may be to touch a metal surface on it. Mains powered gear should have an earth connection to the chassis.(1) It won't save you from any charge you build up between there and your next grounding episode however. You will still get the shock with this method, if you use your finger, so onto the foreign object section of the post.

The bags mentioned above are good, but you might feel odd walking around with one. A (metallic!) paperclip will do just as good. Hold the paper clip, then touch the cubpoard/tap/metal surface etc. You can be a little more discreet this way. There's also the added bonus that if you do it in a dark room, you may even get to see the spark jump from your paper clip to the object in question, without feeling anything yourself. A malicious person may walk around with a paper clip and touch other staff members with said paperclip, possibly giving the victim a shock while feeling nothing themselves. This sort of childish behaviour should not be condoned.

Of course, you may also feel odd walking around with a paperclip. Depending on your job, there may be other metallic stealth-discharge-rod's you could keep on your person, for example a screwdriver (just make sure you're holding the shaft, not the insulated handle), some keys, a stapler (!), metal rule......

(1)There's no guarantee that any particular bit of gear will adhere to this requirement, and, depending on your country of residence and/or the competence of your electrical contractor, the earth may or may not be present. Good old trial and error may be your best friend here.

[Titana]

Hum.... Well, I have heard that electrons can build up on your body by rubbing your shoes on a carpet, resulting in a negative charge. And until there was someway for the electrons to leave your body, you remain charged. One of the ways this charge can leave your body is by touching a doorknob or something like that, because touching a doorknob provides a path for the electrons to move toward a place with positive charge.

And yes, as many already mentioned carrying something made of metal around would definitely help.

Titana.

[Sticks]

I thought it was the rubbing off of electrons, thus building a positive charge

[JohnD]

You think static is uncomfortable, but not dangerous?
Did you see a recent Brainiac?

After proving that it was unnecessary to ban mobile phones in a petrol forecourt (ringing twelve in a petrol soaked caravan - Brainiac hates caravans - didn't set anything off) they set up two wires in the caravan, with spark gap in between. One end was held by a Brainiac, who danced about in a plastic bowl, wearing a nylon rain jacket and trousers. He then touched the end of the other wire.

BOOOOOOOOOM!

Very satisfying!

John

[Krevel]

I thought it was the rubbing off of electrons, thus building a positive charge

It's a weird artifact from the early days of study into electricity. The 'hot' pole was called the positive and the grounded pole is the negative. I guess that this was before anyone figured out that electricity is moving electrons, which are of course, negative. So the positive terminal of a battery is actually the one with the excess electrons. Confusing, eh? That's why its more accurate to use cathode and anode.

Speaking of paperclips. What if you hung one off of your pant leg so that it would drag along the carpet? Wouldn't that keep you from acquiring a charge in the first place?

Oh, and if everyone in your office takes to wearing electrostic bags over their hands, please post a photo, Sticks!

[Titana]

I thought it was the rubbing off of electrons, thus building a positive charge

Hum, well, let me start from the beginning. Usually an atom contains as many electrons as protons. If, however, a surplus of electrons builds up on the atoms of an object, then the object becomes negatively charged. If electrons leave an atom (or object) the atom (or object) becomes positively charged......




Titana.

[JohnOAS]

Hum, well, let me start from the beginning. Usually an atom contains as many electrons as protons. If, however, a surplus of electrons builds up on the atoms of an object, then the object becomes negatively charged. If electrons leave an atom (or object) the atom (or object) becomes positively charged......

Two atoms are sitting at the bar. One says to the other:
"I think I just lost an electron."
"Are you sure?" is the reply.
"I'm positive!"

[Titana]

Two atoms are sitting at the bar. One says to the other:
"I think I just lost an electron."
"Are you sure?" is the reply.
"I'm positive!"

Titana.

[ryanmercer]

most commercially sold carpet is loaded with chemicals, and account for the thick black smoke when your house is on fire.

This also one of the main reasons fermaldyhyde levels (and other chemical levels) are far higher inside your house than outside in a rather polluted area.

[ryanmercer]

Two atoms are sitting at the bar. One says to the other:
"I think I just lost an electron."
"Are you sure?" is the reply.
"I'm positive!"

Hahah

[John Dlugosz]

Try getting a small digital termometer that also shows humidity. If it's extremely low, you can argue that that's not healthy in and of itself. A small humidifier got rid of the sparks in my home, which I run if I have to use the heater.

You could also try surrounding yourself with a cloud of ions. Assuming this isn't woo-woo.

--John

[Taks]

re cell phones: biggest joke i've ever heard. i'm usually tempted to intentionally make calls standing in front of the signs that say "turn off your cell phone when pumping gas" simply to point out the sheer stupidity of the hysteric. a serious lack of science goes into these moronic decisions.

also, you think static is bad where you live, try colorado springs... ugh. i get shocked several hundred times a day. even when the relative humidity is 50%, it is still drier than anywhere else at 10%. the atmosphere at 7000 ft. just can't hold any moisture... it's usually actually below 20% here, btw. working with high-end electronics (stuff i design) is difficult, but the anti-static tile we have works pretty well. i do wear static straps when i'm working with something i don't want to fry, however.

taks

[Jim]

There is a story from the early Seventies about a company that had just installed a computer room at its headquarters. They had purchased a main frame IBM... y'know, the one with all those reel-to-reel magnetic tapes to store data? It was housed in a climate controlled, carpeted room.

They fired up the computer and it worked just fine. After a couple of days, though, they noticed that the computer was losing data. Not lots of data, but small bits from different files.

An investigation found that the cause was static discharge.

Miniskirts were all the rage with women, and they wore nylon panty hose under them. As the female employees walked past the computer, their thighs rubbed together. This generated a static charge in the nylons, which discharged into the magnetic tapes, erasing random bits of data.

Technology thwarted by Fashion.

[Sticks]

So what was the fix?

[Taks]

So what was the fix?

i hate to say it, but the answer may be censored.

taks

[NEOWatcher]

So what was the fix?

A new computer?