When it comes to electromagnetic radiation, I'm afraid the first thing you think of is microwave ovens and induction cookers. For microwave ovens, there is usually a complete metal shell with a small protective plate outside the fuselage. In addition, the sliding door of the microwave oven has a protective lock, so the microwave leakage is limited. Moreover, when using the microwave oven, few people need to stick to it and stare at the food, so it is less harmful to people.
In contrast, the electromagnetic radiation of induction cooker is much more open. The induction cooker will produce extremely low frequency electric and magnetic fields during its operation. Because it is separated from metal heating objects, the electromagnetic radiation of induction cooker is several tens or even hundreds times higher than that of ordinary household appliances, but fortunately, the radiation of induction cooker is upward. In other words, as long as the side shield of the induction cooker is safe and effective, and the operator keeps a certain distance from the side, there is no problem in normal use. However, when using the induction cooker, people need to keep a close distance, so its radiation impact is far greater than that of TV and computer.
Because there is no relevant standard of extremely low frequency electromagnetic field in China at present, the radiation degree of induction cookers in the market is unknown. Professor Zhu Changshou from the Institute of Radiation Protection and Nuclear Safety Medicine of China Center for Disease Control and Prevention told reporters that radiation can be roughly divided into ionizing radiation and non-ionizing radiation. In addition to ionizing radiation, most of our families are faced with non-ionizing radiation, among which high-frequency radiation has the greatest influence on people.
Diversification of TV pollution
Speaking of TV, the radiation pollution of TV has a long history. In people's traditional ideas, the "skill" of traditional crt TV pollution is the most profound, because it has not only electromagnetic pollution, but also radiation pollution and light pollution.
Everyone who has dismantled the TV knows that crt TV has a big lead shell outside the cathode ray chamber at the back. Why is TV the top of e-waste? This is because every crt TV has a lead block structure. The reason why this structure must be used is to prevent radiation from the cathode ray chamber. However, according to Professor Zhu Changshou, radiation is inversely proportional to the square of the radiation distance, and the radiation will decay rapidly with the increase of the distance. Therefore, in the viewing distance of more than one meter, the electromagnetic radiation pollution of TV to people is not great. And the TV screen has a strong ability to absorb all kinds of radiation. Usually, the radiation outside the screen 10cm is very small.
In fact, the biggest radiation of TV comes from the side and back, but fortunately, we don't go behind TV when we watch TV at ordinary times. When pregnant women are watching TV, it is best to switch on the TV and wipe the screen for the prospective father. Professor Zhu said that LCD TV and other products do not have this radiation problem, but it is worth noting that in fact, the light flicker and brightness change produced by TV are most likely to cause fatigue of people's vision and nervous system, and even cause diseases. When we are alert to the ubiquitous radiation, we should actually pay attention to the light pollution caused by TV.
Mobile phone pollution is still inconclusive.
Cell phone radiation definitely exists. How to make a phone call without radiation? Some time ago, the leader of Xiaoji brought a radiation suit, and Zhu Xiao did an experiment. When the mobile phone was wrapped in clothes, the phone was always disconnected. This shows that this dress really works, and secondly, the mobile phone is really a radiation.
Although cdma now says that the radiation is lower than gsm, PHS says that it is lower than cdma and gsm ... In fact, even the fixed telephone itself has radiation. What can be compared between mobile phones?
But at least we know that Bluetooth headsets and wired headsets can really keep us away from mobile phones. If the mobile phone is at a distance from the TV and speakers, the interference will be much less, so it is not harmful to the health to stay away from us. Some studies even claim that putting a mobile phone in a coat pocket can easily lead to heart disease, and putting it in a trouser pocket can easily lead to infertility. In fact, there is no unified conclusion at present. What we have to do is to rationally keep a certain distance from them.
In fact, it is normal for electrical appliances at home to have radiation. Generally, after keeping a certain distance, radiation has little effect on people. Unless you live under high-voltage power lines and next to the relay station of mobile communication, it will have little effect on your health. Professor Zhu Changshou told us that radiation, like fire, is not good to get too close. No matter what household appliances you use, as long as you control the distance, radiation pollution will not find you.
Computers and network cables can be shielded.
Computers and network cables also radiate to the outside world. The internal current of the network cable is weak, and most of the network cables are shielded. Therefore, when the network cable is connected to the computer or embedded in the wall, the radiation of the network cable can be basically ignored.
The radiation of the computer is not very high. Although the power of cpu, graphics card motherboard and other components are hundreds of watts, and the board is completely bare, it does not actually produce much radiation. The main radiation of the computer comes from the radiation of the transformer coil and the radiation of the display in the power supply part.
The radiation of the transformer is not large, which is generally obvious when the machine is turned on and off. Because it is located in the deep part of the chassis and the opening direction is backward, the power supply rarely affects people. On the contrary, the radiation of the display is more direct to people. Radiation display is still dominated by crt products. But unlike the TV, you should keep a distance of less than one meter when operating the computer. If you are far away, many small details on the screen can't be seen clearly. This brings a problem, perhaps the visual damage caused by the monitor is higher than that caused by the TV!
At a distance of more than one meter, radiation has no effect, but the visual stimulation caused by flicker and brightness change still exists. Working and playing in this environment for a long time has far more influence on vision and brain than watching TV.
The purest light pollution
Nowadays, light bulbs are used less and light tubes are used more. Have you ever tried to point a digital camera at a night light? You can simply try it, and you will find that the lights in the display screen are flashing, just like the effect of the camera on the TV. This is because most of the lamps we use are powered by alternating current, and stroboscopic phenomenon is more common.
In fact, the light of the fluorescent lamp we use is stable. Professor Zhu introduced that as long as the light is constant and the eyes adapt, it is usually not easy to cause visual fatigue. The visual effect of fluorescent lamps is still in dispute. But what is certain is that working in light for a long time and working in natural light for a long time have absolutely different effects on vision.
In addition, not long ago, the reporter also saw a slightly blue energy-saving lamp. This kind of lamp is dazzling, and the lighting is ok. Never use it as a light bulb.