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Does it matter whether you wear your anti-static wrist strap around your wrist or around your ankle?

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    \$\begingroup\$ Only if you have artificial limbs. \$\endgroup\$ – Spehro Pefhany Oct 26 '16 at 10:41
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    \$\begingroup\$ Why not both, wrap a third one arround your head. \$\endgroup\$ – Marko Buršič Oct 26 '16 at 10:46
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    \$\begingroup\$ I was thinking about one at each toe. Or did you mean it seriously? \$\endgroup\$ – Marty Oct 26 '16 at 10:47
  • \$\begingroup\$ Related question on SU: How to properly use an antistatic wrist strap when working on a desktop PC? \$\endgroup\$ – BlueRaja - Danny Pflughoeft Oct 26 '16 at 15:21
  • \$\begingroup\$ @MarkoBuršič When I worked at a professional electronics workstation, we were required to wear anti-static ankle straps (with loops inside our shoes), anti-static lab coats, and anti-static wrist straps which we had to connect to the anti-static mats that covered every surface whenever we were working. \$\endgroup\$ – Brian Knoblauch Oct 26 '16 at 18:18
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It makes no difference where you connect the anti-static strap to your body.

The reason is that your body is much lower resistance between any two points than the strap is.

Also, most of the resistance between any two points on your skin is getting thru the skin at each point. You're just a bag of saltwater (electrically, anyway). The bag has a resistance of a few kΩ to a few 100 kΩ from the outside to the inside, but once inside, the saltwater effectively shorts everything together relative to the bag's resistance.

So the body adds negligible total resistance to the strap, and resistance between any two points on the body is largely independent of where on the body those two points are. It's really about how dry the skin is at the connection points, not where the connections are.

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  • \$\begingroup\$ Anti-static shoes work on the basis that damp feet in sweaty socks should be enough to contact you to the shoe which contacts you to the floor which itself will be anti-static in the lab. Unless I was meant to be wearing anti-static socks which no one told me. The test point seemed happy enough. Wrist bands were also worn when doing sensitive work. Anyway the point being that grounding your feet or ankles is fine just as this thorough answer shoes, I mean shows. \$\endgroup\$ – TafT Oct 26 '16 at 15:01
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Electrically, it doesn't matter where it makes contact, with contact being the key word! I find however that it doesn't suit my workflow round either wrist or ankle.

If worn on my wrist, the trailing wire interferes with stuff on my bench. If worn on my ankle, it's a long way down to attach and detach, and being out of sight, it's easy to be working for a while at the bench and suddenly realise that I've not been grounded for the last few minutes. Notwithstanding that I am stronger than the popper holding it together, I can still fall over if I walk away from my bench without detaching it. If people come to talk to me from alternate sides, I can contrive to wrap it round the pillar of my revolving chair.

Fortunately my workplace is very tolerant of solutions that work, even if they are unconventional. I wear a gold chain at work, with an attached wire poking out through my shirt front. This is where I clip my grounding lead. It doesn't get in the way, it's easy to reach for on and off, and easy to see to remind me I've got it on, and not to tangle myself in it.

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    \$\begingroup\$ The golden grounded chain will be my first choice from now on. \$\endgroup\$ – Vladimir Cravero Oct 26 '16 at 11:23
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    \$\begingroup\$ I can see an opening for some geek jewellery here. Now, where are my gold plated banana plugs ..... \$\endgroup\$ – Roger Rowland Oct 26 '16 at 12:05
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    \$\begingroup\$ @RogerRowland back in the day when my employer had a gold plating bath (cyanide'n'all) I tried to gold plate a couple of T03 2N3055s for cuff links. Could never get the right prep for the surface though. \$\endgroup\$ – Neil_UK Oct 26 '16 at 13:05
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    \$\begingroup\$ Well, my last geek purchase would have probably pleased you too then! \$\endgroup\$ – Roger Rowland Oct 26 '16 at 13:22
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    \$\begingroup\$ No 'tache, but as for the rest, our mother wouldn't be able to tell us apart! \$\endgroup\$ – Neil_UK Oct 26 '16 at 14:30
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No.

Just be sure that it is properly connected to whatever reference you have around.

The table/bench you work on should also be at the same potential, and if possible also use an anti static mat and chair.

All those does not need to be grounded, but they do need to be connected to the same potential. If ground is available ground them.

You probably do not even need the anti static wrist strap: grab your silicon/boards/whatever and let it sit for a while on your bench. After some time... voila', everything is at bench potential. If you also are at bench potential there is no harm in touching the device without wearing the strap.

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    \$\begingroup\$ Yes, everything should be at the same potential. But you could build up a little static charge, between touching the shielding of the device now and then. A wrist strap ensures you're connected all the time. Wearing the strap around your ankle is more convenient. \$\endgroup\$ – Marty Oct 26 '16 at 11:04
  • \$\begingroup\$ This is correct, and wearing a strap is always a good idea, especially when handling special parts like FIBs or RMAs. If all your equipment is anti static you can probably forget the strap without causing damage. \$\endgroup\$ – Vladimir Cravero Oct 26 '16 at 12:15

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