The ITU Radiocommunication Assembly considering that transmissions in the bands mentioned in considering a) and predominantly those in considering c) provide widely accepted means of distributing time signals and standard frequencies; that for many purposes worldwide time synchronization with an uncertainty of less than 1 ms is required, which in an ideal case should be based on simple and inexpensive equipment; that interference may reduce the usefulness of standard-frequency and time-signal services to a serious degree.