Different types of Radiation
All parts of the electromagnetic spectrum are described as ‘radiation’, but not all radiation is the same.
At the top of the scale, ionising radiation (as in radioactive decay or x-rays) has the ability to alter matter, including human cells. It has very high energy which can change a molecule’s structure. This can have serious consequences – ionising radiation can cause changes in the structure of DNA, leading to mutations and in some cases cancer.
By contrast radio waves, such as in mobile phones are at the other end of the spectrum. They have very low energies and do not have the ability to alter matter, so they are classed as non-ionising radiation.
Non-ionising radiation does not break molecular bonds. It arises from the lower end of the electromagnetic spectrum, from the electromagnetic fields created by radio and television transmissions, domestic microwave ovens, and mobile telephones.
Effects on health
Heating is the main biological effect of the electromagnetic fields created by radio waves. In microwave ovens this fact is employed to warm up food. The levels of such fields to which people are normally exposed are very much lower than those needed to produce significant heating. The heating effect of radio waves forms the underlying basis for current guidelines. Scientists are also investigating the possibility that effects below the threshold level for body heating occur as a result of long-term exposure. To date, no adverse health effects from low level, long-term exposure to radio waves or power frequency fields have been confirmed.1
It is noted that electromagnetic fields above certain levels can trigger biological effects. Experiments with healthy volunteers indicate that short-term exposure at the levels present in the environment or in the home do not cause any apparent detrimental effects. Exposure to higher levels that might be harmful is restricted by national and international guidelines.
According to the World Health Organisation (WHO), over 25,000 articles have been published on the effects of non-ionising radiation over the past thirty years. “Based on a recent in-depth review of the scientific literature, the WHO concluded that current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields”
The guidelines on exposure to electromagnetic fields are set by the International Commission on Non-Ionising Radiation Protection (ICNIRP). This body, which is recognised by the WHO, reviews scientific literature from around the world and produces guidelines from this work. 2rn strictly adheres to these guidelines at all of our sites.
Everyone is subjected to magnetic fields even within the home. Microwave ovens, TV sets, radios, and even the vacuum cleaner, all create electromagnetic fields which emit small amounts of non-ionising radiation. The amounts emitted are very small and well below the accepted international threshold level (100_T).2 Outside the home, security tag systems in shops, metal detectors in airports etc. Also create electromagnetic fields which are well below the threshold.
An important point to bear in mind is that electromagnetic fields diminish the further one is from the source. Mobile telephone base stations create electromagnetic fields. These fields are created by the antennas, which are normally at least 15m from the ground, as they transmit signals parallel to the ground to mobile phones. At ground level, the electromagnetic radiation level is very small and well within guidelines. In fact, the exposure level is 1/5 that of a domestic microwave oven.
The role of Comreg
The Irish Commission for Telecommunications Regulation (Comreg), takes compliance with international guidelines on exposure to non-ionising radiation very seriously.3 To date, several audits of sites have been undertaken by Enterprise Ireland, as a standards body on behalf of Comreg, to evaluate the measures that site operators have in place and the actual levels of non-ionising radiation produced. These audits have been based on large samples of sites around the country. All operators have appropriate procedures in place and the levels of non-ionising radiation are well within guidelines.