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Anti-static wrist straps come in 2 flavours: fabric strap or metal band. A metal band is more expensive, but is it better? Or is it just for cleanrooms?

  • The fabric strap is attached to a little metal piece which makes contact to your skin to conduct static electricity away. The fabric strap itself often has a surface resistance of +/-1E5 ohm on the inside and +/-1E12 ohm on the outside.
  • The metal band makes contact around your whole wrist, because it's made of stainless steel all the way around. It's very conductive on the inside, but the outside is often painted.

Is there any change of static build up on the insulating outside of a stainless steel anti-static wrist band?

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  • \$\begingroup\$ Antistatic straps should have a resistance if about 1E6 Ohm to ground (uually using a resistor on the wire) to revent user electric shock if they touch mains etc potential objects. Doing this while hard grounded is a very bad idea. So 1E5 in strap proper is irrelevant. \$\endgroup\$
    – Russell McMahon
    Oct 26, 2016 at 10:50
  • \$\begingroup\$ The 1E6 ohm resistor you're talking about is between the (very conductive) metal part of the wrist strap and the grounding wire. The fabric strap itself (attached to the metal part) often has a surface resistance of +/-1E5 ohm on the inside and +/-1E12 ohm on the outside. \$\endgroup\$
    – user127725
    Oct 26, 2016 at 10:54
  • \$\begingroup\$ Yes. The extra 1E5 in the discharge path is 10% of the resistor to ground. So if calue were exact you'd get 1.1 megohm. 1.1 = 1 here :-). \$\endgroup\$
    – Russell McMahon
    Oct 26, 2016 at 11:00
  • \$\begingroup\$ The metal ones probably last longer. Fabric ones loose their stretch. \$\endgroup\$ Oct 26, 2016 at 11:24

1 Answer 1

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The point about static electricity is that there's usually not that much energy, i.e. charge, building up over a short time.

Therefore, a couple kOhms resistance don't make that much difference - your body voltage would break down over that.

I'd argue that the fabric ones are better for most usage scenarios: they are simply more comfortable to wear, and that makes a difference in usage, and also, humans become sloppy over time – and that'll lead to you being more likely to take off the wristband "earlier".

Is there any change of static build up on the insulating outside of a stainless steel anti-static wrist band?

I'd say: no. Not at all. Ok, it depends on the conductivity and thickness of that lacquer, but assume the following. I'll try to draw a worst case scenario.


You take your angora bunny to your workplace.

Wikimedia Commons: English Angora

For some reason, that bunny gets aggressive/bitey when you don't pet with your wrist, so you pet it with your wristband, and by doing so, you're constantly stroking with the outside of your wristband.

Charge builds up on the wristband's outside. However, that charge is either very small, or directly discharges into the metal part.

So you're fine.

Someone notices you and your pet rabbit at work and fires you, but not without offering the position of chief rabbit safety overthinker in his night-time job, organizing rabbit fairs. You become famous and rich.


Not that bad for a worst-case scenario.

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  • \$\begingroup\$ A German with a sense of humor! Now I have seen it all ;-) \$\endgroup\$
    – winny
    Oct 26, 2016 at 10:23
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    \$\begingroup\$ @winny, you should come to Germany :) we've all sorts of humor, highly engineered, as soon as you've got your humor permit, which of course involves a lot of correctly processed application forms! (also, we've got traumatized bunnies with compulsive biting, so better bring sturdy boots) \$\endgroup\$ Oct 26, 2016 at 10:49
  • \$\begingroup\$ @Marty so, charges are everywhere, but it's not a problem as long as the charges are small. also, 5kV isolation probably means "you can touch a live power line with 5kV and won't die", which means that the full thickness of lacquer, at these voltages, might have a couple dozen kOhm; for a static charge, that'll still be enough to discharge through the metal part. \$\endgroup\$ Oct 26, 2016 at 10:52
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    \$\begingroup\$ @RussellMcMahon German humor licenses are practically irrevocable; in theory, you just have to fill a few permit-challenge forms, get them signed by an accredited humor evaluation facility, and then hand them in and wait for them to be processed, then show up in person for the humor-permit-revocation process hearing, but in practice, the ministry that assigns humor evaluation accredition permits is so overloaded that there's not a single institution out there that can accredit humor evaluators, and hence, the two existing evaluators have crazy pricing. \$\endgroup\$ Oct 26, 2016 at 11:22
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    \$\begingroup\$ Optional: a. All or lead intone "we will exterminate you. Exterminate. Exterminate. Exterrrrminate ... or (b.) "We Pentium. of Borg. Division is futile. You will be approximated ... \$\endgroup\$
    – Russell McMahon
    Oct 26, 2016 at 13:03

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