# Fuzzy Decision Algorithm for Health Impact Assessment in a 5G Environment
## 2 Overview of Open Questions, Guidelines, Recommendations, and Standards
### A Brief Overview of ICNIRP (2020) versus ICNIRP (1998 and 2010)  
The comprehensive approach involves consideration of frequency bands, types of adverse health effects, how to set limits, etc. The guidelines indicate permitted RF levelsthat should not be exceeded to ensure health protection. In this part of the paper, the authors provide a comparison between current and previous guidelines (ICNIRIP 1998, 2010, and 2020) and a comprehensive analysis of several studies related to the assessment of non-thermal effects of RF-EMF. ICNIRP (2020) used the same approach as ICNIRP (1998). ICNIRP (1998) set sufficient guidelines for the thermal effects, and ICNIRP (2020) upgraded these guidelines, partially modified them, introduced new restrictions, and reduced or abolished some restrictions. There are two new restrictions for additional health protection in ICNIRP (2020). The first relates to new technologies that use RF above 6 GHz, such as the 5G mobile network. The second refers to short body exposures to RF (\(<\)6 min). The latest edition of ICNIRP took into account a broad frequency range from 100 kHz to 300 GHz. This will ensure that exposures from new technologies (5G mobile networks) do not lead to an excessive temperature rise deep in the body. Intense bodily exposure to RF above 30 GHz can significantly increase the temperature of the local tissue. Accordingly, ICNIRP (2020) provides additional restrictions on energy absorption for the range from 400 MHz to 6 GHz and restrictions on absorbed energy densities for frequencies greater than 6 GHz. These restrictions should ensure that future new high-frequency technologies (5G and 6G mobile networks) do not cause an excessive temperature rise due to short exposure. ICNIRP (1998) provides reference levels for EMF in the far-field and near-field zones (Figure 1), while ICNIRP (2020) provides reference levels for the near-field and far-field zones separately. Figure 1: Reference levels with a shaded 5G high-frequency range [2,6]. ICNIRP (2020) introduced several significant changes to protect against local radiation exposure higher than 6 GHz [7]:  
1. ICNIRP (1998-2010) used \"incident power density\" while ICNIRP (2020) uses \"absorbed power density\";
2. Whereas the previous guideline averaged over a 20 cm\({}^{2}\) region, the new one requires averaging over a 4 cm\({}^{2}\) region (and even up to a 1 cm\({}^{2}\) region); due to the emergence of new technologies (5G and 6G mobile networks), ICNIRP (2020) introduced a restriction of 1 cm\({}^{2}\) for the calculation of highly focused beams above 30 GHz. Since the degree of focus increases with frequency, restrictions below 30 GHz have not been defined because the beams are not focused enough to cause harm;
3. ICNIRP (2020) does not recommend the averaging time reducing with increasing frequency, as it makes a poorer estimation than that predicted by the additional \"short exposure limit\";
4. Instead of incident power density restrictions defined in ICNIRP (1998), ICNIRP (2020) provides absorbed power density restrictions for equivalent maximum body exposures above and below 6 GHz. The advent of 5G technology has been a significant advancement in telecommunications. It offers faster Internet speeds, increased bandwidth, and lower latency. However, as 5G networks continue to expand, there are increasing concerns about the potential health risks associated with this technology. 5G technology relies on higher frequency radio waves than previous generations of wireless technology, which means that more energy is needed to transmit signals. This increased energy creates more electromagnetic radiation, and the proximity of the 5G antennas, which are expected to be placed much closer together, creates a higher risk of exposure to electromagnetic radiation. ICNIRP (1998) included whole-body reference levels for electrical and magnetic fields and power densities above 10 GHz, while ICNIRP (2020) does not consider these fields for whole-body reference levels above 2 GHz.