EMP stands for Electromagnetic Pulse. EMP is the transfer or electromagnetic energy from one source to another in such a way that it causes damage. As such EMP is something technians must address.
There are 3 types of EMP:
1. Electrostatic discharge
2. Electromagnetic Inteference
3. Radio frequency interference
Electrostatic Discharge (ESD)
Electrostatic Discharge is abbreviated as ESD. ESD is when you pass static electrical charge from one item to another. ESD is more commonly known as static electricity. If you’ve ever been shocked when you touched a doorknob, car handle, or someone else, you’ve experienced ESD. While the small shock may not hurt you, this shock can damage delicate computer components. ESD occurs when two objects with different amounts (potential) of static electricity come into contact with each other. Thus to avoid ESD you need to keep yourself and the computer components at the same electrical potential. This is called grounding yourself. You can ground yourself by wearing an antistatic wrist strap connected to your computer, such as the power supply. One end of the wrist strap has an alligator clip for you to clip onto a metal plate on your computer. The other end is attached to a small metal plate that is secured to your wrist.
Antistatic mats are also used to control ESD. You can place computer components on antistatic mats while in the process of repairing the components. Antistatic mats and wrist straps use resistors that stop the flow of electric to prevent a static charge from racing through the components.
However, when a computer component is not actively in use, it’s best to store them in antistatic bags. Antistatic bags are specially desiged to get rid of static electricity.
Low humidity (dry) and cold environments commonly cause ESD to occur. The ideal humidity range for computer equipment is between 50-80 percent.
Electromagnetic Interference (EMI)
Electromagnetic Interference is abbreviated as EMI. EMI is when a magnetic field interferes with electronics. EMI can cause the picture on CRT monitors to become distorted. EMI can also get in the way of data transmission over copper wires, like network cables. Strong EMI is capable of permanently wiping data off of hard drives or any form of magnetic media. Prevent EMI by keeping computer equipment away from magnets. Note that we may not know when magnets are present. For example, any device with an electrical motors has a magnet. Telephones and power bricks for your laptops may even have magnets. Other sources of EMI are high voltage transformers, electrical panels, and fluorescent lights.
Note that ESD can destroy hardware, whereas EMI usually only causes temporary problems and is more dangerous to data than to hardware.
Radio Frequency Interference (RFI)
Radio frequency interference is abbreviated as RFI. If you’ve ever heard strange noises when using a baby monitor or radio, you may have experienced RFI. Many things like cell phones, wireless network cards, cordless phones, baby monitors, and microwave ovens emit radio waves. When two devices are sharing the same radio requency, they sometimes interfere with each other which can cause poor signals. RFI doesn’t destroy anything but can prevent transmission.