AN055
ESD Static Protection Manual
6
materials such as plastic bags or Styrofoam containers can generate severe static electricity
and are not suitable for use in operating areas, especially ESD protected area (EPA). The act
of peeling tape from a roll of tape can generate 20,000 volts. Even compressed air blowing
on insulating surfaces can generate static charges.
Table 1-1. Common Static Sources
Things
Electrostatic material
Working desk
Waxed, paint or paint surface
Untreated polyethylene or plastic
Glass
Floor
Potting concrete
Waxed or finished wood
Floor tiles and carpets
Clothing and
person
Non-ESD protective clothing
Synthetic material
Non-ESD protective shoes
Hair
Seat
Finished wood
Polyethylene material
Glass fiber
Insulated wheels
Packaging and
Handling materials
Plastic bags, packaging,
envelopes
Foam bag, foam plastic
Polystyrene plastic
Non-ESD protective boxes, trays,
containers
Assembly tools and
materials
Pressure injection
Compressed air
Synthetic brush
Heat gun, hair dryer
Copier printer
Destructive electrostatic discharges are often initiated by adjacent conductors, such as
human skin, and onto the conductors of the assembly. This happens when a human body
with electrostatic charges comes into contact with a printed board assembly. Electronic
components are destroyed when static electricity is discharged through the conductive pattern
to ESD-sensitive components. Much lower than the electrostatic discharge that the human
body can feel (less than 3500 volts), it can still damage ESD sensitive components. Typical
electrostatic voltage generation strengths are shown in
