Exposures from base stations

Radio frequency (RF) fields spread out from an antenna high on the supporting structure, like a beam of light from a lighthouse. The RF field strength is greatest close to the antenna at the height level with the antenna. Where necessary, our base stations have signs, barriers and other controls in place to restrict access to this area. There is a ‘blind spot’ between the beam and the mast where exposure is very low. At ground level, the RF field strength initially increases as the distance from the base station grows. After it peaks, it reduces rapidly as the distance increases.

This means that, when an antenna is placed on a rooftop, be it on a house, school or office, the people in the building directly below receive very low exposure. The area where people receive the greatest exposure is typically between 50 and 200 metres away, depending on the height and angle of the antenna. However, this is still a fraction of the recommended limit for public exposure to RF from base stations set by the International Commission for Non-Ionizing Radiation Protection (ICNIRP) guidelines.

All our base stations comply with the ICNIRP guidelines. The power of an individual base station varies depending on the area covered, but is typically between 2 and 150 watts. Micro-cell base stations that give extra coverage and capacity in busy areas, and in and around buildings, usually have a power of between 1 and 2 watts. This means people’s maximum exposure is usually between 0.01% and 2% of the ICNIRP guideline limits for public exposure. Even people who live or work near a base station are not exposed to more than this amount.

The World Health Organization (WHO) fact sheet on base stations and wireless technologies concludes that "there is no convincing scientific evidence that the weak RF (radio frequency) signals from base stations and wireless networks cause adverse health effects". The WHO has no plans to conduct further research into the effects of RF exposure from base stations, as it is not considered necessary.