Electromagnetic environments in high-rise office buildings

In the recent years the electromagnetic environment in high-rise office buildings has attracted greater attention. It is of concern because of the potential for interference with sensitive equipment, and the possible health impact on occupants. This paper discusses the issue and presents results of surveys of extremely low frequency (ELF) magnetic fields in high-rise office buildings. Office equipment and lighting systems generate localised fields, but heavy current-carrying conductors can produce substantial fields over a wide area, including areas where sensitive equipment is located. It is found that the magnetic fields are generally in the range of a few milli-Guass in office areas, but in areas close to heavy-current carrying equipment the fields could reach several hundred mG. Some key design issues for electrical power distribution are outlined.