We have all seen Electro Static Discharge (ESD) in the form of lightning or perhaps felt the zap when reaching for a door knob. Similar types of electrical charges can have an effect on the electronic components you handle every day inyour work. Unfortunately, their effect is much more hazardous and not as readily apparent. Listed below arepreventative steps to use in dealing with static sensitive devices.
1. Be ESD awareness trained and certified.
2. Process ESD parts/assemblies at a certified ESD protected work station.
3. Wear a static neutral/dissipative smock covering all clothing from the waist up.
4. Wear a wrist strap, grounded smock, or foot strap on each foot
(a
wrist strap must be worn whileseated).
5. Test daily the wrist strap or foot straps and log results, or use
a continuous-monitoring system. If the testfails or continuous-monitoring
alarm is set off, replace the discrepant
strap immediately.
6. Verify wrist strap ground connection before exposing ESDS parts.
7. Keep bench mats clean.
8. Keep non-conductive ESD generating material and personnel items out
of the ESD protectedarea/workstation.
9. Essential materials/instructions shall be kept greater than 12 inches
from exposed ESDSdevices/assemblies.
10. Conduct taping operations in an ionized air stream.
11. Package and keep all ESDS devices/assemblies in static shielding
bags or static shielding covered toteboxes when not being processed.
Shielded tote boxes used in a cleanroom environment shall bewashed after
each production order with a commercial grade cleaner. Static shielding
bags shall be free of tears or holes along any seam or surface. Exposed
metallized surfaces are functional when free of bare spots.
12. Move ESDS devices/assemblies between areas in ESD protective packaging
or using a
cart with adrag chain.
13. Never leave unprotected ESDS parts/assemblies unattended.
14. Protect failed parts from further damage by handling and packaging
with the same care
as a new part.
15. Pick up ESDS devices preferably by the body of the component instead
of by the leads and only when grounded at an ESD protected work station.
Whenever possible avoid activities
that result in sliding ESDS devices
on surfaces or against one another.
16. Under no circumstances touch an operator that is holding an ESDS
device/assembly. Transfer of ESDS items shall be accomplished by placing
the item on the grounded work surface and
then picked up by the second
grounded person.
17. Make certain “visitors” to the area comply with ESD
requirements.
18. When the relative humidity has been determined to be <30%, stop
work and place all ESDSdevices/assemblies in protected packaging until
informed that the humidity has
increased to >30%.
19.
Computer and oscilloscope screens shall be placed a minimum of 24 inches
from exposed ESDSdevices/assemblies.
20. Report any discrepancies or non-functioning protective devices and
any condition that may compromisethe ESD program to a supervisor or
lead.