What are the most common forms of electromagnetic radiation?
What is electromagnetic radiation
The interaction between electric and magnetic fields generates electromagnetic waves, and the phenomenon of electromagnetic waves emitting or converging into the air is called electromagnetic radiation. Electromagnetic radiation is a substance that exists in a special form that is invisible and intangible. The Earth, where humans live, is itself a large magnetic field, and its surface thermal radiation and lightning can generate electromagnetic radiation. The sun and other planets also continuously generate electromagnetic radiation from outer space. The natural magnetic fields, sunlight, household appliances, etc. surrounding humans all emit radiation of varying intensities.
When electromagnetic radiation energy (represented by field intensity) is controlled within a certain limit, it is not only harmless but also beneficial to the human body, organisms, and other organisms. Whether it is harmful to the human body mainly depends on the frequency and power of electromagnetic radiation. Only when these two factors exceed a certain allowable value and cause radiation pollution, can they potentially have a negative impact on the human body. According to the 304 Fact Report "Electromagnetic Fields and Public Health Base Stations and Wireless Technology" released by the World Health Organization in May 2006, there is no convincing scientific evidence to prove that weak radio frequency signals from mobile communication base stations and wireless networks can have harmful effects on biological health, given very low exposure levels and research results collected so far. It can be seen that electromagnetic radiation is not directly equivalent to electromagnetic pollution, let alone directly linked to human health.
What are the sources of electromagnetic radiation
Our common electromagnetic radiation sources include radar systems, television and broadcasting transmission systems, radio frequency induction and medium heating equipment, radio frequency and microwave medical equipment, various electrical processing equipment, communication transmission stations, satellite earth communication stations, large power generation stations, transmission and transformation equipment, high-voltage and ultra-high voltage transmission lines, subway trains and electric trains, as well as most household appliances.
Microwave ovens, computers, televisions, hair dryers... These household appliances, which are closely related to people's lives, all generate electromagnetic radiation. Compared to computers, household appliances, and professional electrical equipment, base stations are not one of the stronger radiation sources. Especially based on the application of digital technology, the radiation intensity of 3G mobile communication has been further controlled. According to authoritative testing, the electromagnetic radiation of a normally powered on laptop is approximately equal to the radiation of two communication base stations. The radiation output of a working microwave is 40 times that of a communication base station.
The higher the base station density, the smaller the radiation
The most commonly used 2G, also known as GSM mobile communication, uses cellular technology. Mobile phones and base stations are connected in both directions through electromagnetic waves, and each base station has a certain range of functions. To ensure good call quality, it is necessary to establish multiple mobile base stations in multiple locations and increase signal coverage. And the recently popular 3G technology, whose base station is actually a low-power transceiver, is a regular radio wave, usually only 5-40 watts, much smaller than the thousands of watts of television transmission towers. Some citizens are concerned that the more base stations built in residential areas, the greater the radiation. According to Yeter Anger, an expert from the Swedish National Radiation Protection Association, people's anxiety is entirely caused by unfamiliarity with new technologies and is a misconception in their understanding. In fact, the higher the density of the base station, the lower the power transmitted by the base station. Meanwhile, the closer to the base station, the lower the transmission power of the mobile phone. That is to say, the more base stations are built, the less radiation people receive from telecommunications equipment. Because base stations are dense, communication signals will be better, so mobile phones don't have to work hard to release signals. It's like in a specific environment, when two people are talking up close together, they can hear clearly without having to shout loudly. Generally speaking, people do not need to worry about the adverse effects of radiation on the human body when they are 1-3 meters away from a 3G base station.
