Page 5 - Treston workspaces

ESD - Electrostatic discharge

In ordinary movement a person creates static electricity. are sensitive to charges of 100...200 volts. The presence
In these circumstances hand contact with a conductive of inherent ESD is not easy to detect. Product-related
material will discharge static from the body very rapidly. defects can often be latent and become active over time.
This is ESD = Electrostatic discharge. Static electricity An unbroken ESD safety chain is essential to guarantee the
has become a major problem in the electronics industry. quality of the final product. An ESD-protected production
Usually this passes unnoticed because our bodies do chain is called an EPA (= ESD Protected Area). Employees
not feel discharges below 3000 volts. We may see ESD must be able to implement the right policies in an ESD-
above 5000 volts as a spark. protected work environment.

The most sensitive components may be damaged by a
charge of just 30 volts, and many standard components

CHARGES GENERATED ON DAILY WORK ACTIVITIES

Walking across a carpet 1 500 – 35 000 volts

Walking over vinyl floor 250 – 12 000 volts

Working at a bench 700 – 6 000 volts

Picking up a plastic bag from bench 1 200 – 20 000 volts

Chair with polyurethane foam 400 - 3 000 volts

The lower the relative humidity the higher the voltage. The lowest values in the table usually apply when the relative humidity
is 65-90%. During a cold winter day, the relative humidity in indoor spaces can be as low as 10 %.

Treston - ESD workspaces 5