Most of the radio frequency (RF) fields spread out from a high antenna, like a beam of light from a lighthouse. There is a shadow area between the fields and the mast. 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 a mast 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, in fact, 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).
All our base stations comply with the ICNIRP guidelines. In fact, people’s maximum exposure is usually between 0.01% and 2% of the ICNIRP guidelines for public exposure. Even people who live or work near a base station are not exposed to more than this amount.
A Group Policy on the Health and Safety of RF Fields has been implemented at all local operating companies. It deals with the potential health and safety risks that may arise from employees and the public being exposed to RF fields – particularly when very close to the antenna, where the RF field strength is greatest. As a result, where necessary some base stations have signs, barriers and other controls in place to restrict access around the antenna.