Hi everybody,

One of our internal specifications states that processing equipment needs to
be "electrically isolated" from the static dissipative mat.  We are
interpreting this to mean that if the equipment has a metal case it is not
allowed to be in contact with the mat.  There has been some controversy over
this, because we have whole areas and labs that have test equipment and
other items that do not have the little feet on the bottom and make contact
with the mat.

We have people arguing on both sides here.  Some say that the contact
provides a direct path to ground taking out the resistance needed to slow
down the discharge.  I say that the dissipative (rather than conductive)
nature of the mat provides the necessary resistance.  That is why resistors
are no longer required in ESD specifications.

Others say that the equipment can inject electrical energy through the mat
into the ESDS devices.

What do you all think?

Thanks,

Jim Jenkins

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