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I have a cheap ESD mat and wrist band which I use behind my desk with a computer/Arduino breadboard setup. However, my components are 1 to 2 meters away (since my desk is full).

I need to take off the wrist band and the ESD mat stays on the desk ... what is best? To roll my office chair towards the desk with components or to walk? The floor is wood and normally I wear rubber/leather shoes.

The risk I see is that components I pick up at the other desk can get static energy because of rolling my desk chair or walking to the desk (and picking up the components on that desk).

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    \$\begingroup\$ Just hold your hand against something grounded (a large mass of metal, like a cabinet, would probably be enough) before touching the components. Other than that, walking is probably fine. \$\endgroup\$
    – DerStrom8
    Commented Apr 24, 2017 at 10:32
  • \$\begingroup\$ I don't have that around nearby, however, I can easily make a grounded wire towards one and touch it. \$\endgroup\$ Commented Apr 24, 2017 at 10:34
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    \$\begingroup\$ Where is the risk that you think you identify? I'm not seeing a risk in your words. \$\endgroup\$
    – Andy aka
    Commented Apr 24, 2017 at 10:34
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    \$\begingroup\$ Did you already killed some device, or you just can't sleep at night because of ESD beast? \$\endgroup\$ Commented Apr 24, 2017 at 10:54
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    \$\begingroup\$ You could also try a longer esd wristband cable ;) \$\endgroup\$
    – PlasmaHH
    Commented Apr 24, 2017 at 11:05

2 Answers 2

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The risk I see is that components I pick up at the other desk can get static energy because of rolling my desk chair or walking to the desk (and picking up the components on that desk)

Never pick up a component up that is static sensitive unless it is in its proper packaging or is placed on a conductive mat that you can initially discharge your finger/body to. While touching that mat you can pick up the component and any charge you might acquire on the return journey from that desk to the other desk is of no consequence providing to acclimatize your body potential to the target circuit you are going to put that component in.

This is all helped by the use of earthed wrist bands because it guarantees a degree of protection without having to think what you are doing. Removing the earthed wrist band means you have to think about what you are doing and, of course, doing things in the correct order is important.

What is unsalvageable is a component removed from its protective packaging and placed on a non-conducting surface. You cannot subsequently guarantee what charge that component has acquired so even if you use a wrist strap it doesn't offer much protection. Always handle components correctly and always place them on something that offers conduction even if it isn't earthed. While handling them always connect your body first to the conductive protection rather than the component.

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  • \$\begingroup\$ Thanks, it seems I have to either extend the cable from my wrist band so I can get a bit further, or take the plastic box with all components, walk back, touch the ESD mat and pick the component out of the box and place it on the mat. I don't want to spend money to make all packages ESD safe (which means in practice that all ICs are placed on white/pink foam and in unprotective boxes). But the ESD mat / wrist band was like 15 euro so that's acceptable what I want to invest. \$\endgroup\$ Commented Apr 24, 2017 at 11:30
  • \$\begingroup\$ Regarding the "unsalvageable" scenario, couldn't you just safely equalize that component's potential with the mat through a resistor? While only handling it with plastic tweezers or gloves to do that? \$\endgroup\$ Commented Apr 14, 2021 at 14:14
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Any time you are moving something ESD sensitive, it should be completely enclosed in a static bag. Heel straps wont cover it you need two and doesnt insure you are grounded at all times. Need a special floor anyway. Same goes for chairs, need to be ESD safe chairs that drag a chain on the special floor. Put the device in the bag, fold/close it, then remove wrist strap, walk or roll to next station, put that wrist strap on then you can open the bag.

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  • \$\begingroup\$ If that's the case maybe I should get rid of my ESD mat anyway and just take a loss now and than :-) \$\endgroup\$ Commented Apr 24, 2017 at 13:30
  • \$\begingroup\$ Depends on how paranoid you want to be and the cost of the unit. I have worked in environments where we had to be very paranoid. Big metal objects grounded chassis are not the solution, note, it is about the speed at which you discharge your energy that does the damage, the mats and straps have some resistance that controls that speed, just touching a computer chassis or the screw on a light switch plate, etc is not the answer for example. You are going to generate the energy just sitting there working, so a one time grounding doesnt to it either. \$\endgroup\$
    – old_timer
    Commented Apr 24, 2017 at 13:38
  • \$\begingroup\$ I carry personal boards around all the time, mcu eval boards, etc take my chances with those, work stuff that costs 10 to thousands of times more, thats a different story... \$\endgroup\$
    – old_timer
    Commented Apr 24, 2017 at 13:40
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    \$\begingroup\$ that mat is good to have either way, if nothing else it subconsciously reminds you that this is a work space and to treat it differently than a desk or dining room table, etc... \$\endgroup\$
    – old_timer
    Commented Apr 24, 2017 at 13:54
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    \$\begingroup\$ BTW you asked the question so I answered....Sometimes ESD protection is well taught, sometimes not...It can cost money to get paranoid about it, including regular calibration/testing, so weigh that against the real cost of losing product. Even at a buck a board if you start zapping a bunch of them then something to think about but if you have gotten this far, or keep going for years and never knowingly killed one, then is it worth the expense? \$\endgroup\$
    – old_timer
    Commented Apr 24, 2017 at 13:58

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