A radio quiet zone is an area where radio transmissions are restricted in order to protect a radio telescope[1] or a communications station[2] from radio frequency interference. The Radio Regulations of the International Telecommunication Union (ITU) define interference as being detrimental to radio astronomy if it increases measurement uncertainty by 10%. In particular, the applicable regulation is known as ITU-R Recommendation RA.769, "Protection criteria used for radio astronomical measurements".[3] Equipment that can cause interference includes mobile phones, television transmitters, and CB radios, as well as other electrical equipment.[1]