Hello All Experts,
One of our customer has provided a requirement that ESD footwear, wrist straps, and garments must be checked on a daily basis.
We are already checking ESD footwear and wrist straps daily at every EPA entry.
Please advise and support us on how we can check the ESD garments on the ESD turnstile at every EPA entry.
Rahul,
In order to test your garments at the ESD turnstile you would need to have the type of garment that has both elastic cuff sleeves as well as a groundable point snap. If you don’t have this, the only other way to test the garment per ESD TR53 is to lay the garment out on an insulative support surface and measure cuff to cuff (limit being < 10^11 ohms per ANSI/ESD S20.20).
If you have garments with elastic cuff sleeves as well as a groundable point snap, then you could get a cord that has one end that snaps onto the garment and the other end that can go into the ESD turnstile test point (e.g. banana jack). One issue you could run into is the limits set into the ESD turnstile integrated checker. If it is set for wrist straps the limit is < 3.5 x 10^7 ohms. If you are using the garments as a groundable static control garment, the limit per ANSI/ESD S20.20 is < 10^9 ohms so you may see some false failures depending on your garment. There are some integrated checkers that have separate checking functions for wrist straps and garments so you would not have this issue.
Thanks a lot Mr. Andy for your valuable inputs.
It means we need to change the garment type from static control garment to groundable static control garment.
Once again thanks a lot for your continuous support and guidance.
Rahul,
You could also try to convince your customer that you only test your garments monthly or after washing. See section 7.3.16 in ESD TR53 for the method. If you are forced to buy new garments you may also need to buy a new integrated checker to ensure the higher garment limits of < 10^9 for the static control garment or met. Thanks