There are many types of anti-static wrist straps, such as from iFixit ($8 via Amazon), but most have the same components. There’s an adjustable wrist strap with conductive material, and a cord with a built-in resistor. You wear the strap and connect the cord to a grounding surface.
These special wrist straps help to prevent the buildup of static electricity, which can damage sensitive electronic components and other devices that might be worked on.
Have you ever felt (or even seen) a small jolt when shuffling across carpet and touching a door knob, another person, or any other object? Static electricity can damage or destroy sensitive parts.
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There’s also a style of wrist strap that’s said to be anti-static, but without any cords or wires.
I don’t know how they are supposed to work. The whole point of an anti-static wrist strap is to provide a pathway for built-up electrical charge to flow to ground. That prevents a build-up of charge that could choose its own path to ground, such as through your fingers and a potentially sensitive electronic component or device.
Looking online, there are many negative user reviews saying that don’t work.
There’s also a new NASA report about the matter. Unfortunately, their alert and testing doesn’t seem to be public, but the conclusions are.
According to results from testing performed by the NASA Interagency Working Group on Electrostatic Discharge (IAWG-ESD), it was confirmed that wireless wrist straps failed to prevent charge build up or to drain accumulated charge in order to prevent potential discharges. Wireless wrist straps do not meet American National Standards Institute (ANSI)/ESD S20.20 Wrist Strap System performance requirements and therefore are not acceptable for use in ESD controlled areas used to process critical NASA mission hardware.
So, there you have it.
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I can see the appeal in working with a cordless or wireless wrist strap. But it seems that they don’t actually work.
Read More(via NASA)
Michael Quinlan
Maybe they should now turn their attention to the effectiveness of upgrading from corded to cordless tools by simply cutting off the cords?
John Sullivan
That’s damn funny! (referring to M. Quinlan’s comment)
Having said that, I wonder if it is feasible to engineer a wireless antistatic device which captures the electrical charge to a battery, with a tiny motor or LED array to use up excessive charge?
Cole Kemp
That’s exactly what I thought about when I started reading. The only thing I could see happening with a motor is that it may actually be likely to create a electromagnetic field or send a current out of the motor.
Koko The Talking Ape
I think a sharp metal needle pointed outward could bleed some charge off into the air. But the effect would be tiny.
You could also attach one end of a capacitor to your body, to absorb a bit of charge. But it still wouldn’t zero out your charge. It would absorb charge until the overall potential is equalized, like flowing water. It would be like trying to drain a flooded basement by adding another room to it.
Or you can connect something to you that has the exact same charge but with opposite polarity, to cancel you out. But how would it know how many electrons or holes are needed?
I wonder if just touching one end of a battery would do it. Your excess electrons or holes would flow into the battery. You would still have a charge of 3 V or 6 V or whatever volts the battery is, but it wouldn’t be 20,000 V that static charges can be, that destroy electronic components. If you aren’t sure which end to touch, just touch both. Would that work?
Greg
To remove a charge from anything you need a current path for current to flow.
You would have to provide an opposite charge and a conductive path for the charge to flow.
You could store the charge in a capacitor but you would need an opposite charge locally in the wrist strap to pull the charge of you. that would have to be recharged, and be extremely complicated.
It’s very very very simple to touch something conductive.
skfarmer
is anyone really surprised by this?
pete
probably the people that have bought them…….. lol i have not bought any
glenn
No.
dajkyyc
You would not believe how many factories I’ve found in China that swear by these things.
I’m glad that I’ve found other documents to prove that they don’t work.
I’ve shut down manufacturing of our company products when we’ve caught suppliers trying to get away with using these. There are name brands that are selling these things in Asia.
One manufacturer builds products for commonly recognized consumer brand.
charles
the same people that thought the stick on cell phone antenna boosters bought these wireless antistatic wrist straps. and zombie repellent spray.
Tim
I’ve never seen a zombie since I bought the repellent!
Jim Felt
The classic “too good to be true syndrome”.
And we have non other then NASA weighing in. Good for them. And I’ll bet someone in their sphere asked about the logic of an ungroundable wrist only device. No?
Stuart
The article mentions subcontractors. So either their personnel, or subcontractors’ must have been asking about them, or tried them for personal projects.
Or it could have come from another department or person, with NASA having the right equipment to test things out.
Jonathan
The anti-static straps that I use the grounding tip (vs banana clip) is actually a long ground prong/plug that is basically the same size as the ground prong on a US grounded cord that would plug into a 20A or 15A receptacle. It plugs into the ground hole of an outlet (Yes, I HAVE CHECKED that all outlets in my house I don’t have ant open or hot neutrals and the grounds are truly grounded).
A tiny bit of water with some salt dissolved rubbed on your skin and on the metal contact points will improve the conductivity. I also wear mine on my ankle rather than my wrist, as it provides a flatter and more consistent contact with my body, but more importantly it does’nt get in the way or catch on things when I’m working.
Speaking about grounding and Humans, every notice how refreshing you feel after swimming in a river or the ocean or even just walking or running (as a kid) around outside barefoot in the grass?
That is the grounding effect (discharge) from excessive postive ion build up in your body and nowadays we are walking positive ion capacitors because of our lack of contact with the surface of the Earth.
Grounding actually drains off the buildup of positive charged ions – it’s a natural antioxidant that drains off or negates free radicals in our bodies. Better natural direct contact with the Earth or water in contact with the Earth than thru an electrical panel connected to grounding rods or water supply.
The excess buildup of positive ions results from rubber shoes and all the other insulated flooring and footwear as well as our modern day exposure to the plethora of electronics in our lives.
Humans used to walk barefoot or wear leather soled shoes and sleep on the ground and work the Earth with our hands and we used to run or walked barefoot on a more frequent basis.
I’m not a doctor nor do I play one on TV or the internet, but next time to have lower back pain or a severe migraine try sitting or walking barefoot in moist grass for 15 min, or if your ambitious soaking your feet in a creek.
Granted this in not backed up with the gold standard of a double blind study mind you but plenty of anecdotal evidence, (btw free) but many have found it effective at reducing the inflammation in thier bodies inflammation can causes a myriad of symptoms and pains. It’s akin to the people that had injuries that feel when a storm is coming from the change in barometric pressure. We human are extremely senstive to our enviorments and exposures (i.e. OSHA) .
That said some may say it’s junk science, but consider all the electrical reactions or connections in our body from cells to the Ca- Mg+ reaction that contracts and relax our muscles to the natural pacemaker that sense a electrical charge to make our heart beat.
Pardon my digression on a tool website, but one thing that many of us share in common are sore muscles and body aches and pains.
Greg
My dad is a big believer in grounding too, apparently he read a book on it, though it was called Earthing.
https://www.amazon.com/Earthing-Most-Important-Health-Discovery/dp/1591202833
Jonathan
That is where I got the ground straps that I use mainly for Electronics, but I do work the earth in my business and I do try walk barefoot as much as possible. I don’t sleep with any of the earthing/grounding items.
The inefficacy of ground straps or electronics that have been damaged, I would venture to guess is as much end user error or improper use i.e. lack of contact with skin or using a ground that is not truly grounded, or end user were’nt wearing a ground strap during and ESD event and said they were. Most ground wires straps seem to use a pretty 26-28 ga twisted wire. If ground straps did’nt (i.e. in housing going to ground rounds sunk to the proper depth for the surrounding moisture content of the soil (meeting the bear minimum for code). Yet ground faults do occur hence the installation of GFCI.
firefly
I much prefer the the ankle strap as well. Back in the day when I build my own server I have always put down an ESD ground mat along with wearing an ankle strap.
As far as science… the best science is the one that work for you.
Bryan
Avionics techs at my work use them all the time. Doubtful if this new information was shown to my company that they would change their ways though.
Tyler
I didn’t know such a thing existed. What is their claim on how it works? Do they try to stuff the charge into a capacitor and bleed the charge off with a resistor?
Farid
You would either have to provide a path to a lower potential but large reservoir , hence the cord on a conventional strap tied to an infinite reservoir (ground). Or, have a generator that generates opposite polarity charge. But how does the generator determine the amount of charge on your body ?? That’s probably why they don’t work so well.
Wayne
A couple of winters ago, I got a wrist-strap tester. All my wrist straps failed. Then I used some ESD lotion (that was previously unknown to me) where the straps wrapped my wrist. Then they all passed, easy-peasy. And I use the elaborate expanding watchband types, with metal all around, which I figured just always worked.
A dry environment will cause more static and more dry skin, of course, and that lotion worked! Maybe any lotion would help, but this stuff was specific. Cheap, too.
https://www.amazon.com/Lotion-Pregloving-Antistatic-Moisturizing-Bottle/dp/B008EEJ6L8
Farid
That is a good lesson. Do not assume that you are bind discharged just because you have a wristband on. I have the same issue every time and I have the metal ones too. I found out that any lotion works; even spit! We use a similar lotion at my work.
Benjamen
Good point about the lotion, I remember there being lotion bottles on the production floor where I used to work. I think technicians had to wear straps, but I never wore them when I went to the production floor because plugging in was a pain in the butt.
ESD smocks were required though, they have conductive fabric woven in to equalize the charge across your torso. I think these are probably way more effective.
Also all of our tables had special surfaces that were tied to ground.
I think another measure is proper humidity control. If you don’t let the humidity get so low ESD is less of a problem.
Benjamen
The other problem with most consumer wrist straps is that they are single conductor. With the single conductor you can’t tell if there is a break in the wire.
A dual conductor like these: http://www.qsource.com/p-26945-transforming-technologies-wb0050s-metal-dual-conductor-wrist-strap-small.aspx forms a circuit when it’s plugged in.
If the circuit is broken a LED turns red and there’s usually an audible beeping from the base station.
firefly
The wireless anti-static wrist straps work great for protecting my hand tools. I have also used on my garden tool. So far it has protected all my garden tools from any ESD damage. Highly recommended! 😀
Hang Fire
Never trusted them, stuck with the old grounded resistor straps.
Mention should be made of not just the existence, but the reason and importance of the resistor- it keeps people from getting electrocuted.
ktash
Dogs often get static electricity shocks. Too bad this doesn’t work, it would be nice to have a dog collar.
glenn
Really? just touch a water tap and save your money.
o
Barks
Pex and pvc and other plastics go to ground?
dandLyons
I was a NASA engineer. I worked on the Mars Science Laboratory spacecraft that delivered the Curiosity Rover. We had to suit up in order to work on flight equipment. We wore metal corded wrist straps & ESD lab coats. We tested the wrist straps each and every time we put them on. The lab environment was monitored. We ran ionizers if the humidity was too low. A quality assurance engineer monitored our every act. There are meters for monitoring the presence of electro-static fields.
We also wore hats, boots, gloves and masks so as not to contaminate the equipment with biological matter. You don’t want someone to sneeze on a piece of equipment & then send that flu virus to Mars. Equipment is cleaned and periodically monitored for contamination. This process is referred to as “planetary protection”, namely protecting other planets from us.
Everyone undergoes training with re-qualification required at regular intervals. There are literally a few thousand people working on every aspect of these projects at any given moment.
NASA routinely sets standards and policy on these things and reiterates them often.
For example, you know those pink plastic bags and pink foam packing material that are supposed to be “anti-static”… yeah, uh … not so much. Those are banned by NASA. If you want to safely store some components, look for 3M static shielding bags. They have a laminated metal foil. Digikey carries them.
I also worked in the semiconductor industry where I was involved from initial testing of prototypes to final delivery w/ full reference designs. In both industry & at NASA, the pcb assembly areas are under strict ESD control. PCBs would be assembled using pick & place machines and SMT parts where possible & hand assembly where needed. As an engineer submitting a design, you would kit the necessary parts and deliver them for assembly. While some parts such as resistors and capacitors are not ESD sensitive, you needed to strip away any potential ESD hazards such as packaging materials. So we would bag all the components in 3M shield bags. You can attach labels that match the components to your Bill of Materials & by part number, component values, & schematic reference designators. You can also simply write on the bags with a Sharpie marker. Once all the parts were bagged, we would put them in an ESD tote and deliver it. For prototypes you are initially only building one or two but you often order pcbs based upon economies of scale. So you kit parts for the full number of pcbs. That way you can always take the remainder of the kit back to assembly and have them build up more boards.
The nice thing about the 3M shield bags is that you can reuse them. If you write on them with Sharpies, you can wipe it clean with alcohol.
I once worked with a contractor who was storing some lab stock semiconductors (not flight hw parts) in plastic containers. I called it to his attention. Without hesitation, he said that he “didn’t believe in static electricity”.
NASA is ever vigilant in protecting hardware from faulty equipment and bad practices… even to the point of having to weed out the occasional ESD denier.
Farid
….“didn’t believe in static electricity” yeah…and a carbon film resistor is the same as a metal film, as long as the resistance values are close enough, and tantalum caps are the same as polyester and will be just fine in space equipment. It’s all good.
What a moron, Gosh, I hope he is not a commercial avionics supplier?!
Jonathan
Do you know if the contractor was also a moon landing denier as well?
If yes, perhaps someone has a red pill they can offer to the contractor. 😉
Krazy Kanuck
Apparently cordless bungee jumping doesn’t work either…
Norm Huizenga
Just a thought, maybe change the main image (the one you see on the home page, to the actual wireless strap). I thought at first, you were talking about the wired straps. Maybe even a bad/good image to nail home the point, like so: https://i.imgur.com/rzAiKXZ.png
Stuart
Thanks – good idea, and I’m sorry for the confusion! I can that my arrangement was less than ideal. I swapped images on the front page and added captions. I can’t upload new images at the moment though, the server is acting up, but I can try later.
Jonathan
LOL, I also completely missed the wireless/cordless aspect of the ESD straps. I wasnt even aware they made a wireless/cordless version had I processed it, I would have checked if it was 4/01/18.
Considering that the human body can build and discharge shocks in excess of 3KV with the right combo of humidity and material friction, I could see how they could easily fail or not work, or stop slowly discharging the build-up, moat capacitors and batteries have a finite storage capacity and have to be drain or discharged before they can absorb anymore voltage. I imagine it would be difficult to beat the planet Earth.
If a wireless cordless grounding system existed, and was truly effective, I imagine the US Military would be using them with our Helo’s, special forces, and earth/ship based landing crews, as a fail-safe to the grounding/earthing wands.
gjames
Take your shoes off when working on sensitive items and stand directly on concrete, that’s what I have always done.
Farid
As long as you are working on unenergized circuits, otherwise, it is more dangerous for you. Straps have a resistor in series for a reason.
Farid
Another use for grounding straps is to ensure that you do not accidentally cause a fire while transferring flammable material with low flash point.
Grounding straps and clips are commercially available for containers and bins and OSHA has some requirements under (CFR) 1910.106(e)(6)(ii). There is a short article about it on Grainger’s website (https://www.grainger.com/content/qt-safety-bonding-grounding-255).
Back when I was in college, I severely burned one hand from such an incident.
Chris
A cordless ground strap , sounds about as sensible as a single station intercom with a privacy feature !