FAQs
What are the electromagnetic waves?
ANSWER: These are the well-known radio waves used by radio, television and other technologies in our day-to-day life. Various applications have been used by man for more than 100 years and each day they are used to operate household appliances (such as radios and televisions), to operate cordless phones and in medical applications. Moreover they are used in telecom systems by the fire brigade, police, ambulances and in radar systems. The most recent application of electromagnetic waves, emerged in the 1980s and 1990s, is their use in mobile telephony and satellite communications. back to topWhat exactly is the HERMES Project?
ANSWER: The HERMES Project is an innovative system for constantly measuring and monitoring the electromagnetic radiation from radio frequencies emitted to the environment by all sources located in the area where the system is installed. Using this system one can obtain 24 hour basis measurements and recordings of all electromagnetic radiation in a specific geographical area from various sources such as radio and television station transmitting antennas, mobile telephony antennas, radars, etc. back to topWhich bodies are involved in implementing the Project?
ANSWER: The NTUA Mobile Radio-Communications Laboratory and the AUTH Radiocommunications Laboratory are in charge of the overall technical operation and the scientific aspects of the HERMES Project. The two universities (a) ensure that the results of the measurements are valid and (b) check and confirm that the system is working properly from a technical viewpoint. System equipment has been kindly donated by the mobile telephony provider, Vodafone and before any equipment is included in the system it is checked by the university laboratories. What criteria are used to select the locations where measuring equipment is installed?
ANSWER: There are multiple criteria for selecting areas covered by the HERMES Project, the most important ones being high population concentrations and the special features of the installation sites. For example, it is preferable to install a measurement station at a school building rather than in some uninhabited location at the top of a hill. back to topHow do the monitoring stations work and what electromagnetic radiation sources do they monitor?
ANSWER: The monitoring station is comprised of an electromagnetic broadband radio frequency sensor which covers the frequency band 100 KHz - 3 GHz and an embedded device which processes, stores and transmits the measurements to the central control stations. Data is transmitted once a day via a modem which connects the monitoring station via the GSM mobile telephony network to the central control stations which are installed at the NTUA and AUTH laboratories. The monitoring devices measure and record the spectrum within which mobile telephony, radio and television operate. back to topHow is the validity and transparency of the measurement results guaranteed?
ANSWER: The NTUA Mobile Radio-Communications Laboratory and the AUTH Radiocommunications Laboratory are in charge of the overall technical operation and scientific aspects of the HERMES Project. As independent scientific bodies, they are responsible for the fidelity of the published information. back to topHow is the proper functioning of the monitoring stations guaranteed?
ANSWER: The NTUA Mobile Radio-Communications Laboratory and the AUTH Radiocommunications Laboratory are in charge of the overall technical operation and scientific aspects of the HERMES Project. As independent scientific bodies, they certify the monitoring stations and check that they are operating properly. back to topIs there a plan for applying the Project in other regions of the country?
ANSWER: The objective of the HERMES Project is to cover as many areas of the country as possible. Bodies such as schools, parents and guardians associations and representatives of local government authorities can submit a request in writing to the relevant universities asking for the Project to be extended to cover locations of interest to them. back to topAre there safety limits for electromagnetic radiation exposure levels in the RF band?
ANSWER: International scientific organisations such as the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the World Health Organisation (WHO) evaluate scientific research and then issue strict guidelines designed to protect the public from exposure to electromagnetic radiation (ICNIRP Guidelines Health Physics, April 1998, Vol.74). The specific guidelines have been adopted by the European Union (EU) in a Recommendation issued on July 12, 1999 (on the limitation of exposure of the general public to electromagnetic fields (0 Hz to 300 GHz) (1999/519/EC). In Greece there is a recent statutory framework on the installation of mobile telephony and radio-television base stations which is based on the Joint Ministerial Decision which adopted the EU Recommendation (contained in Government Gazette 1105/B/6.9.2000) and Law 3431/2006 on electronic communications and other provisions (contained in Government Gazette 13/A/3.2.2006) which sets the limits currently applicable. back to topHow is radio frequency (RF) radiation measured?
ANSWER: RF fields have electric and magnetic components. It is frequently necessary to express RF field strength in terms of each component part. For example, the measurement unit Volt per meter (V/m) is used for electric field strength while the Ampere per meter (A/m) is used to measure magnetic field strength. Another quantity that is often used is the power flux density. Power flux density is defined as the power per unit of surface area. For example, power flux density can be expressed as watts per square meter (W/m²) or milliwatts (one thousandth of a Watt) per square centimeter (mW/cm²). back to top |