Static electricity is the accumulation of an electric charge (produced by friction) on a non-grounded object. The static charge on the surface of a non-grounded object can jump when it contacts the surface of any grounded object. This electric discharge is known as electrostatic discharge (ESD). ESD can be very destructive to a computer.
The threat of ESD begins when the fragile components (including the processor, hard drives, memory, motherboard, and expansion cards) inside the computer are exposed. Damage can occur simply by placing a fingertip too close to a component inside an open computer case. ESD charges can travel through wires and into components, where the wires can explode or fuse together, causing the components to fail. ESD can cause immediate failure of components, or could gradually degrade components, causing only intermittent problems.
Implement the following measures to protect against ESD.
- Keep the relative humidity between 40-70% and temperature between 72-77 degrees. Avoid dry air in the computer repair location.
- Use antistatic mats under the PC and on the floor.
- Discharge yourself before touching any computer component.
- When touching anything inside the computer, wear an antistatic wrist strap that is attached with an alligator clip to the metal PC chassis.
- Ground both yourself and the computer to the same ground. This provides a single path for the flow of electrical potential.
- Use static resistant materials to handle computer components.
- Never touch the metal connectors on a circuit board.
- Keep computer repair location free of materials that accumulate electric charges (for example, plastic or Styrofoam).
- Store sensitive components in static-shielded bags (also called anti-static bags; they are usually tinted gray). Static resistant bags are not near as effective (usually tinted pink or blue).
- If a wrist strap is unavailable, keep your body in constant contact with the metal frame when working inside the computer.
Note: Unplug the system before working on internal components. Do not rely on the power cord for an electrical ground.