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As mentioned here, I am a novice to electronics, and I am currently building a wooden workbench. The workbench will have an ESD bench mount and ESD matting over the entire bench. Furthermore, the floor is hardwood flooring.

In a comment by DKNguyen to this answer, it is mentioned that my fabric chair is a "no no" when it comes to ESD safety. In particular, I will be working with some sensitive components, like laser diodes, so I am indeed concerned about ESD safety. Even so, since money is limited, and since this is a home workshop, I do not want to overdo it with a setup that you would find in professional ESD-safe environments.

The problem is that ESD chairs seem to be very expensive, costing around $1000. However, I did find this "Dissipative Chair Cover", which is far cheaper than the ESD chairs; would putting such dissipative chair covers over non-ESD chairs be sufficient for ESD protection, or will I actually need a full "ESD chair"? If the chair cover is not sufficient, then what should I be looking for in an ESD chair? I found some "ESD chairs" that have the following description: "does not feature the conductive plastic components and steel components with conductive coating found on our other ESD models"; does this make them insufficient for ESD protection?

And, lastly, is it sufficient to just have an ESD chair without ESD-specific flooring?

I would greatly appreciate it if people would please take the time to help me with this.

The Pointer
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    This is a shopping question which is off-limits on this site, but I think we can give you some guidelines whether you buy a chair or DIY. We cannot get involved in selecting a product to buy, as this is out-of-bounds for us. –  Jun 25 '20 at 01:30
  • @Sparky256 Thanks for the clarification, Sparky256. Is my edited post acceptable? – The Pointer Jun 25 '20 at 01:32
  • Much improved by not asking us to recommend product A over product B. This is something we cannot do. –  Jun 25 '20 at 01:34
  • @Sparky256 I understand. – The Pointer Jun 25 '20 at 01:34
  • I use a stool. Wood is probably best but I usually have a solid polyurethane which isn't ideal but more comfortable. It's the sliding in and out of a fabric chair on dry days that's really bad. – DKNguyen Jun 25 '20 at 01:44
  • @DKNguyen Any all-wood stool would be sufficient? – The Pointer Jun 25 '20 at 01:50
  • @ThePointer I wouldn't care what anything but the seat was made out of tbh. Metal stools also exist – DKNguyen Jun 25 '20 at 01:50
  • Cheap way: Wrap any chair in aluminium foil and ground it properly. :) – Voltage Spike Jun 25 '20 at 19:38

2 Answers2

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You do not need a full ESD chair IF it has a seat cover or brass mesh that is grounded through a 1 Meg resistor, much like a wrist strap would be, or your wearing BOTH a ankle/heel strap and wrist strap. NEVER directly ground ANY part of your body, because if you do touch something "HOT" you could get a nasty shock. Twice a given voltage will cause it to dissipate 4 times as much energy into your body. 480 VAC will hit you 16 times as hard as 120 VAC.

You have the option to wear ankle/heel straps which keep you safely grounded regardless of chair type, and is what many MFG plants use, along with wrist straps. Once your body is safely grounded your concern turns to making sure your parts containers are the anti-static type.

Do NOT use conventional plastic bags or trays for electronic parts. I have seen many LED's and CMOS IC's get blown this way. If you were doing contracts for NASA then maybe special chairs and netting would be part of the expected cost.

If you are wearing BOTH a wrist and a ankle/heel strap you take yourself out of the static-source equation, so you can pay attention to other static sources such as plastic containers and plastic tools.

  • Thanks for the answer. I have found seat covers that are described as "chair back and seat connected to drag chain", and it is said that this "allows chair to be grounded when on a conductive surface"; is this what you are referring to? Do I just leave the chain to touch the ground and that's it (that is, I don't need to connect it to anything)? There is no mention of a 1 Meg resistor. – The Pointer Jun 25 '20 at 01:48
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    @ThePointer Drag chain is expecting ESD flooring I think – DKNguyen Jun 25 '20 at 01:49
  • @DKNguyen Ahh, ok. – The Pointer Jun 25 '20 at 01:49
  • Yes, the MFG plants I worked in had anti-static paint on the floor. But a MFG has far more resources and liabilities than you do. –  Jun 25 '20 at 01:50
  • @Sparky256 Ahh, ok. Do you think that just using a wooden stool would be sufficient, as suggested by DKNguyen? – The Pointer Jun 25 '20 at 01:51
  • Yes I do. Even a rocking chair. If you are wearing BOTH a wrist and a ankle strap you take yourself out of the static-source equation, so you can pay attention to other static sources such as plastic containers and plastic tools. –  Jun 25 '20 at 01:54
  • @Sparky256 Would the additional ankle strap make any difference? Do I just connect it to the same desk mount https://images-na.ssl-images-amazon.com/images/I/41ElKrP%2BrfL.jpg as my wrist strap ? – The Pointer Jun 25 '20 at 01:58
  • Yes, that is an idea connector for straps. The 1 meg resistor is built into the strap, so it is plug-and-play. –  Jun 25 '20 at 02:01
  • @Sparky256 Ok, thanks a lot for the advice! So wrist + ankle strap and any (even non-ESD) chair would be sufficient? Or should I stick to wrist + ankle strap and wooden stool? – The Pointer Jun 25 '20 at 02:04
  • Why BOTH a wrist strap AND an ankle strap? – user253751 Jun 25 '20 at 17:08
  • @user253751 An ankle/heel strap allows you to get up and move so many feet and still be grounded if you have to disconnect your wrist strap. If floors are painted with anti-static paint then you can walk anywhere and still be grounded. –  Jun 25 '20 at 19:14
  • then don't you only need the ankle strap? – user253751 Jun 25 '20 at 20:03
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I had never heard of ESD chairs, and never been told I need to use one. They weren't even mentioned on my ESD training course.

Most people would use an ESD mat on the workstation and an ESD wrist strap. Alternatively, if you need to walk around a lot, an ESD floor covering and ESD heel strap.

Simon B
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    There are ESD chairs for sure, the chairs also have a chain that drags on the floor to ground it out. There are also ESD floors and ESD foottwear. In aerospace every material has to be ESD material, and if a company does ESD properly you'll also have an ESD smock and humidity control – Voltage Spike Jun 25 '20 at 19:41
  • @VoltageSpike I agree with the close vote. ESD chairs had already been discussed and dismissed. Any more comments or answers would be off-topic or recursive. –  Jun 25 '20 at 23:08