Is the radiation from rooftop communication base stations really that scary?
一、The confusion of communication base station radiation
1. The 'radiation panic' in daily life
In daily life, many people have deep concerns about the radiation problem of rooftop communication base stations, and it can even be said that "talking about base station radiation turns pale". This phenomenon is not uncommon. For example, in the second phase of Fulin Wanjia in Licang District, Qingdao, Shandong Province, residents immediately began to resist and demand that the communication company install a base station on the top floor in an uninhabited area. This is not the first time we have resisted, as we had opposed similar base station installations as early as 2020. There is also the Daye Times Square community in the southern area of Tangshan Road, Hebei Province. 500 residents jointly signed and refused to allow the communication company to build a base station on the rooftop. The reason is that they believe that the internet speed of 5G is hundreds of times faster than 4G, so the radiation should also be hundreds of times faster than 4G. They think that the radiation from the base station will harm the brain and affect physical health.
In many residential areas, as long as there is news of building a base station, no matter how the operator explains that the base station radiation meets safety standards, some residents will not listen and firmly oppose it. Especially for the middle-aged and elderly population, who retire at home and have more free time, it is believed that the radiation from base stations is harmful when chatting with each other, making it very difficult to carry out resident work and install base stations smoothly. However, without base station coverage, the mobile phone signal in the community will deteriorate. For example, some residents in the community previously resisted the construction of base stations, resulting in poor mobile phone signals that even make calls. Nevertheless, they still have lingering fears of base station radiation and are trapped in a contradictory state of both needing signals and resisting base stations. The "radiation panic" has indeed brought considerable difficulties to the construction of base stations and people's normal communication needs.
2. Basic concepts of base station radiation
Communication base station radiation, in simple terms, refers to the electromagnetic radiation of a certain intensity emitted by mobile communication base station facilities through transmission towers and antennas when transmitting signals. It relies on electromagnetic waves to transmit and receive wireless signals in space, thereby ensuring that our mobile devices such as phones can communicate normally. The radiation generated by this electromagnetic wave is the source of concern for everyone.
In fact, radiation is ubiquitous in the natural world we live in. Radiation is usually divided into two types: ionizing radiation and non ionizing radiation. X-rays, CT scans, and other types of ionizing radiation have enormous energy and can alter the structure of DNA. Exceeding the prescribed dose can cause significant harm to the human body; The radiation generated by base stations belongs to non ionizing radiation, just like the radiation generated by common household appliances such as computers, mobile phones, televisions, microwave ovens, hair dryers, etc. It is only a thermal effect and does not damage the molecular bonds of organisms. So, base station radiation is not as terrifying as many people imagine, it is fundamentally different from high-energy radiation that can cause serious harm to the human body.
二、Scientific principles of base station radiation
1. The generation and propagation of electromagnetic radiation
Let's first talk about the principle of electromagnetic radiation generated by rooftop communication base stations. Communication base stations mainly rely on the transmitting antennas on the transmission tower to emit electromagnetic waves outward, thereby achieving the transmission and reception of spatial wireless signals, ensuring that our mobile devices such as phones can communicate normally. In this process, electromagnetic waves bring electromagnetic radiation.
What are the characteristics of its propagation in space? Firstly, electromagnetic waves have attenuation properties when propagating in space. The electromagnetic radiation emitted by mobile communication base stations rapidly decays with increasing distance, meaning that the farther away the base station, the lower the radiation intensity. In areas that people can frequently reach in their daily lives, the radiation level is actually lower than the national standard (0.4 watts per square meter), and it does not pose a threat to the health of residents.
Secondly, the electromagnetic radiation of base station antennas has strong directionality. The electromagnetic waves emitted by mobile communication base stations mainly cover the nearby area in a horizontal direction. Simply put, it is like an umbrella we open, with very little downward energy, and the surrounding buildings also have strong shielding effects on the electromagnetic field. So, the base station antenna built on the roof usually does not have an impact on the residents inside the building.
Finally, there are now many microcellular base stations that have lower transmission power than typical mobile communication base stations, and correspondingly, the electromagnetic radiation intensity in their surrounding environment is also lower than that of typical base stations. In the public activity area near the microcellular antenna, the electromagnetic radiation power density values are all below the national standard limit. Understanding these propagation characteristics can help everyone better understand the actual situation of base station radiation in the surrounding environment.
2. Thermal and Non Thermal Effects
Next, let's talk about the thermal and non thermal effects generated by base station radiation, which can help us scientifically understand the impact of radiation on the human body from the perspective of internal mechanisms.
In terms of thermal effect, when an organism is exposed to a certain intensity of electromagnetic radiation and absorbs it, the temperature of its tissues will increase, and this effect is called the thermal effect of electromagnetic waves. The thermal effect can be further divided into Ohmic thermal effect and fluctuating energy thermal effect. The heating principle of Ohmic heating effect is that free electrons and ions inside the human body move directionally along the direction of electromagnetic wave field strength, and current passes through biological tissues (equivalent to resistance), thereby generating Ohmic heating effect. However, in our normal living areas, the electromagnetic wave energy that the human body can come into contact with is very weak, so the Ohmic heating effect of electromagnetic radiation is generally not significant. The heating principle of the fluctuation energy thermal effect is the friction and heat generation between molecules. For example, the "microwave oven" in our daily life uses this principle to heat food. The microwave oven uses a 2.45GHz microwave signal to irradiate the food in a closed cavity. The water molecules in the food are affected by the external field strength, and the molecules rub and collide back and forth, generating a large amount of heat, thus achieving the purpose of quickly heating the food.
Non thermal effects refer to biological changes in organisms that cannot be attributed to temperature changes after absorbing energy from electromagnetic fields. The essence of non thermal effects comes from the interior of living organisms, and external electromagnetic fields only serve as triggering signals. Electromagnetic radiation safety mainly focuses on the interference of electromagnetic waves on the human nervous system and the penetration effect of electromagnetic waves. For example, in an electromagnetic wave environment with a frequency of 4Hz-1kHz, when the induced current density exceeds 100mA/m2, the excitability of the central nervous system will change dramatically. For safety reasons, in this frequency range of electromagnetic wave environment, the occupational exposure limit induced current is less than 10mA/m2, and the public exposure limit induced current is less than 2mA/m2. But there is no need to panic about electromagnetic radiation in the range of 4Hz-1kHz, because 1kHz electromagnetic wave signals require an antenna at least 75000 meters long to radiate the signal. Such a long antenna is difficult to achieve, so the electromagnetic waves in this frequency range in the environment are very weak.
In short, understanding the thermal and non thermal effects of base station radiation can enable us to view the relationship between base station radiation and human health more rationally, rather than blindly worrying.
三、Radiation standards and safety range
1. Electromagnetic radiation standards in China
In China, there are clear and strict standards for electromagnetic radiation such as rooftop communication base stations. According to the "Electromagnetic Environment Control Limits" (GB8702-2014), the power density of the communication frequency band should be less than 40 microwatts per square centimeter. This standard is applicable to environments where the public is exposed to radiation and is formulated based on long-term exposure. It means that the human body is safe to be exposed to such radiation fields for any period of time, and there is no cumulative effect of radiation.
From the perspective of frequency range, it covers the frequency range commonly used by communication base stations, such as the radio wave frequency range commonly used in 5G signals, which is within the specifications. At the same time, there are corresponding limit values for electromagnetic strength, magnetic field strength, and other aspects. Only base stations that meet these limit values are allowed to be built and operated to ensure public health and allow everyone to live in a safe environment with communication base station coverage under the national standard.
2. Comparison with other countries and common electrical appliances
Compared to countries and regions such as the United States and the European Union, China's base station radiation standards are very strict. For example, the electromagnetic radiation standard for communication base stations in the United States is 600 microwatts per square centimeter, while in the European Union it is 450 microwatts per square centimeter, and in China it is only 40 microwatts per square centimeter, with a very significant difference. This fully reflects the high standard requirements of China in safeguarding public health and controlling electromagnetic radiation pollution.
Comparing the radiation level of base stations with that of common household appliances, many people are worried about the radiation level of base stations, but ignore the radiation situation of common appliances around them. The radiation limit for household appliances such as televisions, computers, printers, hair dryers, etc. with a working frequency of around 50 Hz is 4000V/m; Home appliances such as mobile phones and microwave ovens that operate in the 2.4GHz frequency band are required by national standards to have a control limit of 12V/m. However, China has set the electromagnetic radiation safety standard for base stations at 40 microwatts per square centimeter, which means that the upper limit of base station radiation is less than one tenth of that of induction cookers and much lower than most household appliances. So, from the comparison, it can be seen that the radiation of base stations is within a relatively safe range, so there is no need to talk about base station radiation and feel scared.
四、The actual impact of base station radiation on the human body
1. The impact under normal circumstances
Under the normal operation of the base station and compliance with construction and maintenance standards, the actual impact of the radiation generated on the health of ordinary residents and personnel working near the base station for a long time (such as telecommunications workers) is very limited.
For ordinary residents, they are generally not exposed to high-intensity radiation from base stations for a long time. The radiation levels from base stations that they come into contact with in their daily lives are actually within the range that the human body can tolerate. Just like the common household appliances such as televisions, computers, and mobile phones that produce electromagnetic radiation, the upper limit of base station radiation is less than one tenth of that of induction cooker radiation, and much lower than the radiation generated by most household appliances. Therefore, under normal circumstances, base stations on rooftops do not cause significant harm to ordinary residents.
Taking telecommunications workers who work near base stations for a long time as an example, although they spend more time in the radiation environment of base stations compared to ordinary residents, as long as the base stations are built and maintained according to standards, the radiation level they can withstand is still within a safe range. From scientific research and practical testing, the currently used mobile communication frequencies and power do not cause harm to the human body. For example, the World Health Organization (WHO) has also released a report clearly stating that "no recent research has proven that exposure to radio frequency fields from mobile phones or base stations will cause harm to health. At the same time, China has strict "Electromagnetic Environment Control Limits" (GB8702-2014), which stipulate that the power density of the communication frequency band should be less than 40 microwatts per square centimeter. This standard is applicable to environments exposed to public radiation and is formulated based on long-term exposure. There is no cumulative radiation effect, which also ensures the health and safety of personnel who stay near the base station for a long time.
In short, under normal operation and compliance with relevant standards, there is no need to overly worry about the adverse effects of base station radiation on the body. Base station radiation is relatively safe in daily life.
2. Attention should be paid to abnormal situations
However, we cannot ignore some abnormal situations. If the base station malfunctions or is not maintained properly, it may pose radiation hazards.
For example, when the transmitting equipment of a base station malfunctions, resulting in an abnormal increase in transmission power, or when the shielding device of the base station is damaged, the electromagnetic wave leakage situation may intensify. At this time, the electromagnetic radiation level in the surrounding area may exceed the normal safe range, which may pose a danger to the surrounding residents, such as the occurrence of high electromagnetic radiation levels affecting human health. Also, if the base station lacks standardized maintenance for a long time, key components such as antennas may age or be damaged, and signal transmission may be unstable, it can also easily cause radiation abnormalities.
Therefore, residents should pay attention to the maintenance and management of rooftop base stations, and ensure that operators and other relevant responsible parties strictly maintain and manage the base stations in accordance with regulations. Regular inspections should be carried out to ensure that the base stations are always in normal and safe operation, in order to protect their own rights and health. Once any abnormal situation is found in the base station, such as unknown electromagnetic interference, abnormal signal fluctuations, etc., relevant departments should be contacted in a timely manner to urge them to investigate and solve the problem as soon as possible, in order to avoid potential radiation hazards affecting the health of oneself and surrounding people.
五、Why are base stations built near residential areas
1. Meet communication needs
In today's highly developed information age, people's demand for communication is ubiquitous. Whether it's making phone calls to chat with family and friends, sharing daily life details anytime on social media, or working online, studying online, watching videos, etc., stable and good communication signals are needed as support.
Residential areas, as highly densely populated areas, have a huge demand for communication. The coverage area and the number of mobile phones that can be carried by each base station are limited. For example, in bustling urban communities with numerous residents, the frequency of using mobile devices such as phones at the same time is high. If there are not enough base stations nearby, the quality of communication services will be greatly reduced. For example, in some old residential areas where there were originally few base stations, residents often encountered intermittent calls, network card crashes, or even no signal, seriously affecting their normal life and work.
So, in order to ensure that the communication needs of residents in residential areas can be met and various communication activities can be carried out smoothly, base stations have to be built near residential areas, which is an inevitable choice based on ensuring the quality of communication services.
2. The characteristics of signal transmission determine
The electromagnetic waves emitted by base stations have unique directional characteristics and exhibit the phenomenon of "black under the light". The electromagnetic wave emitted by the base station antenna has a shape similar to a spotlight, which is a slightly parallel electromagnetic beam to the ground with strong directionality. It is very narrow in the vertical direction and decays quickly with increasing distance, resulting in less radiation directly below. That is to say, the base station built on the roof has a building area directly below it that is located in the relatively low radiation "under the light black" position.
Meanwhile, the surrounding buildings also have a strong shielding effect on electromagnetic fields, which can further block and weaken electromagnetic waves, reducing the impact of radiation. For example, in some residential areas, even if there are base stations on the roof, the radiation received by residents living inside the building is negligible, far below the safety limit range specified by national standards.
So from a radiation perspective, base stations built near residential areas such as rooftops are not as close to strong electromagnetic radiation as many residents believe.
