10.2 Electrostatic Discharge (ESD)
10.2.1 ESD defined
Ever gotten a zap from a doorknob in a carpeted room? That is static electricity. Static electricity is the buildup of an electric charge resting on a surface. If there is a buildup of static electricity, it may end up zapping something that can be damaged. A "zap" is formally known as an Electrostatic Discharge (ESD). ESD is the worst enemy of the fine electronics found in computer systems. This is why it has been discussed in almost every chapter in this course.

In order for a person to feel an electrostatic discharge, there must be at least 3000 volts built up. If the discharge causes pain or makes a noise, then the charge was most likely above 10,000 volts. Most computer chips run on less than 5 volts of electricity. If there is less than 3000 volts of static built up, a computer component could be damaged without knowing or feeling it. The table in Figure summarizes some of the important Do's and Don'ts of static electricity. 
 

Worksheet  (PDF, 6 KB) 
  Electrostatic Discharge (ESD)