Definitions: Electromagnetic Interference (EMI)

There are two categories of radio system interaction which concern the regulator.

Electromagnetic Interference (EMI) can be viewed as radiocommunications pollution and is sometimes referred to as "radio frequency interference" (RFI). Reducing the level of EMI produced by electrical and electronic products is particularly important where public safety and security services are involved such as aircraft and ship navigation, fire, ambulance and police communications. Under Article 15 of the International Radio Regulations, regulators are required to "take all practicable and necessary steps" to ensure EMI does not cause harmful interference to radiocommunication services.

Radio transmissions can also cause other non-radio electrical and electronic products to malfunction, a phenomenon sometimes known as "immunity" or "electromagnetic susceptibility" (EMS). EMS can also be a safety of life issue, for example, when the use of cell phones interferes with hospital equipment.