A huge number of antennas (transmitters and recievers devices) systems popping up over the bulding in our neighborhoods, for the internet and communication services. what is the possible risk of overexposure to the radiations resulted from these devices?
Without measuring how much you expose to radio-frequency electromagnetic fields and on which frequency band, it's a bit hard to tell how much you expose from those antennas or any potential risks.
Please read these articles:
https://www.researchgate.net/publication/324968907_Measurement_and_Analysis_of_Power-frequency_Magnetic_Fields_in_Residences_Results_from_a_Pilot_Study
https://www.researchgate.net/publication/277326114_Radio_Hazard_Safety_Assessment_for_Marine_Ship_Transmitters_Measurements_Using_a_New_Data_Collection_Method_and_Comparison_with_ICNIRP_and_ARPANSA_Limits
Engage a measurement from licensed laboratory. We have such in Bulgaria. According to norms in your country the measurement will be under risk level or above. In general, the most of RF radiation absorbed by the body is coming from personal and home based devices, not from roof antennas. For example, pay attention to the dose you get from Bluetooth devices you wear, mobile phones you use, the wireless devices in your home. Again, an in situ measurement may help estimate the dose you are getting.
...tips for protection might be shielding your home or apartment, but such a shield will yield unsatisfactory results, due to the complexity of its construction that is hard to achieve comprehensively.
Dear Malka and Svetoslav,
thank you very much for engagement and the information that you have made,
for Malka question, for the moment I do not have exact measurements or numbers about exposure to radiofrequency electromagnetic fields, but
how much radiation can a human body take, which can be considered below the risk?
State law in Bulgaria defines the following maximum levels of electromagnetic radiation field strength or power density:
30-300 kHz : 25 V/m
0.3-3 MHz : 15 V/m
3-30 MHz : 10 V/m
30-300 МHz : 3 V/m
300 MHz-30 GHz : 10 µW/cm2
Bulgarian levels are one of the most stringent in the world. Nevertheless, no one knows what levels are dangerous, and what are not. Not much is known about the effects of electromagnetic radiation on human health. There are some statistics, that are non conclusive as per my knowledge, that find evidence of serious illnesses among ham radio operators. Others find relation between mobile phone usage and related serious illnesses. You should "dig" for yourself in scientific literature to find more timely and recent evidence and research on this matter.
Dear Salam,
The recent exposure limits are reported in [1]. The Specific Absorption Rate (SAR) and the power-density (PD) reference levels in European countries, USA, Canada, China, Japan and Korea are compared and contrasted. The allowed SAR cellular handsets’ exposure limits for localized heating are more restrictive in the USA, Canada and Korea (1.6 W/kg), relative to others (2 W/kg). Even the averaging is more restrictive: averaged over 1 g in N. America and Korea, versus 10 g tissue in ICNIRP 1998 and ANSI/IEEE C95.1-2006. Europe in general follows the ICNIRP 1998 PD levels from base stations. Despite the (non- mandatory) EU Council Recommendation 1999/519/EC, some EU countries adopt more restrictive thresholds. USA and Japan are the most liberal countries, adopting in 300–1,500 MHz power- density 4/3 of the ICNIRP1998 and IEEE 2006 levels. On 13 March 2015, Health Canada revised the 2009 PD limits (that were identical to the USA), and published more restrictive reference levels. There is no scientific reason to use different exposure limits in different countries. Some explanations of the different limits are provided [1]
References:
[1] H. M. Madjar, "Human radio frequency exposure limits: An update of reference levels in Europe, USA, Canada, China, Japan and Korea," 2016 International Symposium on Electromagnetic Compatibility - EMC EUROPE, Wroclaw, 2016, pp. 467-473. doi: 10.1109/EMCEurope.2016.7739164
[2] ICNIRP, "Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz)," ICNIRP, Oberschleissheim (near Munich), 1998Stars ;
[3] IEEE, "Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz," IEEE Std C95.1- 1999, Washington, 1999.
Dear kenedy,
Your discussion and providing an information to this matter is greatly appreciated
you can find the near reactive field range which depends upon frequency and diameter of antenna. beyond that range you are safe.
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