3.1 Overview of the Assembly Process and Safety Issues
3.1.2 ESD precautions
Electrostatic Discharge (ESD) is more commonly referred to as static electricity. Static charges can build up in the body just by walking across the room. It may not be apparent, but it is usually enough to damage computer components if they were to be touched. A static charge of 2,000 volts is enough for a person to notice. This can be experienced when walking across a room and touching a doorknob or other metal surface. A static charge of only 200 volts is sufficient to damage a computer component. Be aware that damage can be done to a component via ESD without it even being apparent.

ESD is probably the greatest problem when a user is unwrapping newly purchased computer parts and components while preparing to assemble the computer. Always review the ESD precautions before beginning the assembly process. The following recommendations will help to prevent ESD related damage:

  • Keep all computer parts in anti-static bags.
  • Keep the humidity above 50 percent. 
  • Use grounded mats on workbenches. 
  • Use grounded floor mats in work areas. 
  • Use wrist straps when working on computer parts, except when working on monitors. 
  • Periodically touch unpainted grounded metal parts of the computer to lower the static energy of the body.

Remember that just because a discharge cannot be felt does not mean it cannot harm a computer component. Components can be totally destroyed or sustain only minor damage. The latter allows the component to function to some degree or cause intermittent errors. This type of ESD damage is the most difficult to detect. Computer cases, when closed properly, are designed to protect inside components against ESD. They channel ESD away from sensitive components. Basically, any component inside of the computer is susceptible to ESD. ESD becomes a threat when the case is opened and the components inside are exposed, or when the components are removed from the antistatic bags in which they are shipped.

The best way to protect against ESD is to use an anti-static mat, a grounding wrist strap, and anti-static bags. The grounding wrist strap is worn around the wrist and can be connected to the mat. The mat is in turn grounded to a wall outlet. Alternatively, the wrist strap can be clipped to the metal frame of the computer case.