ESD is between two objects. Gounding one self is worthless
unless both objects are grounded.
Even without a ground strap, one can do safe ESD work.
Most people have two hands. Use one hand to equalize charge
and the other to install.
Contrary to what I've see as proper procedure, have electical
contact to both the recieving equipment and the item you are
installing.
As an example. Installing an EPROM. First put one hand on the
progrmmers chassis.
Remove the EPROM but hold the part such that your hand is
touching at least one lead ( power and ground are best )
Hold it in such a manor that any discharge would need to go
through your hand and there it no direct path to the EPROMs
leads ( Faraday shield ).
Place your free hand on the chassis surface of the equipment
you are going to install the chip into. Keep it there until
you have made contact between the leads of the EPROM and
the socket ( sometimes you might need both hands to get the
leads all aligned ). Make sure this is electrical contact.
Connecting everything to a common ground is a good way
and the recommended way in most ESD protection setups.
It is not always best when the people that are handling things
don't understand were and how static charges occur.
I once watch an assembler walk across the room holding
and EPROM at the end of her out stretched arm with no electrical
connection to her body. The leads pointing way from her body.
I couldn't have imagined a worse method for ESD.
The most common source of static is induction. This is usually
seeded with a small charge from friction.
The easiest one to deal with is getting up from a chair. Always
place your hand on a grounded surface and leave it the until
you are standing up. I had one of the lab stools with arm rest.
I found it convenient to wrap wire around the rest and connect
them to ground. It was quite natural to place ones hands on the
rest while getting up.
Surprisingly, connecting one self to ground while seated will
ensure a good charge on your body once you get up. You must
provide a discharge path until you are clear of the chair!!!!
Induced charges are caused buy the separating of thing.
ESD ( electro static discharge)
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