The radiation waves emitted by computers are often ignored by people. According to the international MPRⅡ radiation safety regulations, the radiation exposure must be less than or equal to 25V/m within a distance of 50cm.
But do you know how much radiation the computer is? Computer radiation: 1, keyboard 1000V/m2, mouse 450V/m3, screen 2 18V/m4, host 170V/m5, notebook 2500v/m.
In addition, radiated electromagnetic waves have eight major harms to the human body:
1, the promotion of cell carcinogenesis
2. Hormones are abnormal
3. The calcium ion is violently lost.
4. The initiation of dementia
5. Abnormal pregnancy and abnormal production
6. Hypertension and heart disease
7, electromagnetic wave allergy
8. The increase of suicides
When using a computer, you should pay attention to the four major hazards of computer radiation as follows: )
1, computer radiation pollution will affect the circulatory system, immunity, reproduction and metabolic functions of human body, seriously induce cancer and accelerate the proliferation of cancer cells in human body. `
2, affecting people's reproductive system is mainly manifested in the decrease of male sperm quality, spontaneous abortion and fetal malformation in pregnant women. 2.}N
3. The cardiovascular system affecting people is characterized by palpitation, insomnia, menstrual disorder, bradycardia, decreased cardiac blood volume, irregular sinus heart rate, leukopenia and decreased immune function in some women. 5S
4. It has a bad influence on people's visual system. Because the eyes belong to the sensitive organs of the human body to electromagnetic radiation, excessive electromagnetic radiation pollution will also affect the visual system. Mainly manifested as decreased vision, causing cataracts and so on. Zc=
The results of the latest national supervision and spot check on the quality of computer products announced by the General Administration of Quality Supervision, Inspection and Quarantine yesterday show that the electromagnetic radiation in computers can not be ignored.
The General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) randomly selected computer products from Beijing, Shanghai, Tianjin, Chongqing, Zhejiang, Hubei and other four provinces and cities, and the sampling pass rate was 72%. It is understood that the results of this spot check show that the computing speed, multimedia functions and software and hardware support of computer products in the domestic market have been greatly improved, but the product quality level of some enterprises is not stable enough. In this spot check, the computer products of Stone, Hewlett-Packard, Muze and other well-known enterprises were also identified as unqualified products.
It is understood that the main quality problems found in this national inspection and spot check of computer product quality are that the radiation disturbance and conduction disturbance indexes in electromagnetic compatibility exceed the standard. Radiation disturbance is a kind of electromagnetic wave interference emitted into space when the computer is working, which will affect the normal work of other electrical appliances, especially high-sensitivity electrical appliances. Conducted interference will affect the normal work of other electrical appliances in the same power grid, such as the motherboard, display card, switching power supply, monitor, keyboard, mouse, etc., which constitute the whole system. If it is not well selected, it will cause excessive radiation interference. During the spot check, it was found that some enterprises did not understand the standards well enough, and the control of parts purchase and assembly quality of production lines was lax, lacking the necessary testing means, resulting in unqualified products.
The seven companies, trademarks and models found in this spot check that the radiation disturbance of microcomputer exceeds the standard are:
Beijing Sitong Computer Technology Co., Ltd., Sitong, shocked JS100;
Chongqing Xinbo Information Technology Development Co., Ltd., Xinbo, Freedom Village1101;
Nanning Shengli Technology Co., Ltd., Victory, Leaping Ⅰ;
Shanghai Botai Computer Technology Co., Ltd., Botai, BT-SMC-I 3298;
Wuhan Juxing Computer Co., Ltd., Shennaotong, JXSD530L；;
Beijing Heyuan Muze Technology Development Co., Ltd., Muze, E Fashion 510d;
Shanghai Hewlett-Packard Co., Ltd., HP, P728 1—L2325.
Uncovering the X-files of Computer Radiation
As the saying goes, there is no shortage of gold. Computer, as a modern high-tech product and electrical equipment, brings more convenience, efficiency and joy to people's lives, but there are also some unfavorable factors that are harmful to human health.
From the perspective of radiation types, the hidden dangers of computers to human health mainly include electromagnetic radiation (various electromagnetic rays and electromagnetic waves, etc.), sound (noise), light (ultraviolet rays, infrared radiation and visible light, etc.) and other radiation "pollution".
From the perspective of radiation sources, they include CRT display radiation sources, chassis radiation sources and peripheral equipment radiation sources such as speakers, printers and photocopiers. Among them, the imaging principle of CRT (cathode ray tube) display determines that it is difficult to completely eliminate harmful radiation during its use. Because when it is working, its internal high-frequency electron gun, deflection coil, high-voltage bag and peripheral circuits will produce many kinds of rays and electromagnetic waves, such as ionizing radiation (low-energy X-rays), non-ionizing radiation (low-frequency and high-frequency radiation), electrostatic field, optical radiation (including ultraviolet radiation, infrared radiation and visible light, etc.). Liquid crystal display, on the other hand, uses the physical characteristics of liquid crystal, and its working principle is completely different from CRT display. It is a "healthy" display with no radiation (negligible) and environmental protection. Various components inside the chassis, including CPU with high frequency and high power consumption, various boards with main chips with a large number of transistors integrated inside, optical drives, floppy drives and hard disks with high-speed DC servo motors, several cooling fans and transformers inside the power supply, etc., will emit radiation and noise interference such as low-frequency electromagnetic waves when working. In addition, external speakers, photocopiers and other peripheral equipment radiation sources are also a "source" that cannot be ignored.
Judging from the degree of harm, electromagnetic radiation is undoubtedly the most harmful. Research by medical experts at home and abroad shows that long-term and excessive electromagnetic radiation will directly harm human reproductive system, nervous system and immune system, and it is the main inducement of cardiovascular disease, diabetes and cancer mutation, and the inducing factor of abortion, infertility and teratogenesis in pregnant women, and it can directly affect the development of body tissues and bones of minors, resulting in decreased vision, memory and liver hematopoietic function, and even lead to retinal detachment in severe cases. In addition, electromagnetic radiation also poses a hidden danger to information security, which can be received and decoded by special signal receiving equipment, leading to information leakage and unnecessary losses. Excessive electromagnetic radiation will also interfere with other electronic devices around and affect their normal operation, resulting in electromagnetic compatibility (EMC) problems.
Therefore, electromagnetic radiation has been listed by the World Health Organization as the fourth largest environmental pollution source after water, atmosphere and noise, and it has become an invisible "killer" that harms human health. Therefore, it is imperative to protect electromagnetic radiation.
-------------------------------------------------
]: protection
Spear and shield of health countermeasure A plan
As the saying goes, the devil is one foot high and the Tao is one foot high. In view of the harmfulness of electromagnetic radiation of computers, relevant international and domestic professional organizations and computer manufacturers have started the work of protecting computer radiation very early. After years of hard work, many strict certification standards such as MPR, TCO, FCC, UL have been formulated for the production and manufacture of electronic products such as computers in terms of radiation, energy saving, environmental protection and ergonomics, so as to ensure that human health will not be harmed. At the same time, the so-called "green computer" with energy saving, environmental protection and no radiation has emerged in recent years.
At present, active protection and passive protection can be adopted for the harm of electromagnetic radiation from computers. Passive protection method, that is, in addition to improving the working environment and paying attention to the use method, adopts measures such as providing radiation protection clothes, radiation protection screens, radiation protection curtains, radiation protection glass, etc. for people who often contact and operate computers, so as to reduce or eliminate the harm of electromagnetic radiation; The active protection method starts from the "source" of computer electromagnetic radiation, such as monitors and chassis, to eliminate or shield it.
First, purchase, that is, choose and buy products that meet the "green computer" standard launched by powerful manufacturers on the market; The second is DIY, that is, buying "green" computer accessories that have passed various certification standards to build your own healthy computer. Below we will focus on how to choose accessories that meet the radiation protection standards to DIY healthy computers.
The working imaging principle of CRT display determines that it is difficult to completely eliminate the harmful radiation it emits in use. In order to minimize the intensity of harmful radiation and protect users' health, international authoritative organizations have successively launched a series of anti-electromagnetic radiation certification standards for electronic devices such as displays. From the initial MPRⅠ( 1987), MPRⅡ( 1990), TCO'92( 1992) to the latest TCO'99, TCO'03 (as shown in figure 1), the radiation to the display, and the impact on the display.
At present, there are nearly 20 certification standards related to monitors. Among them, the famous certification standards are MPRⅡ of Swedish National Bureau of Measurement and Testing, TCO series of Swedish Professional Employees Union (TCO), EnergyStar of US Environmental Protection Agency (EPA), FCC of US Federal Communications Commission (FCC) and the latest 3C of China. Let's focus on understanding and mastering the common certification marks on several monitors.
In 1987, the Swedish Bureau of Measurement and Testing certified by MPRⅡ put forward an earliest standard-MPR Ⅰ, on the influence of electric and magnetic field radiation on human health. On this basis, 1990 extended it to MPRⅡ ⅱ, which more strictly limited the magnetic field intensity generated by the display in use, and provided 2 1 item display standards, including flicker, jitter, linearity, brightness, reflectivity and font size, and put forward the maximum radiation of ultra-low frequency (ELF) and very low frequency (VLF) of the display. MPRⅡ standard has become a globally recognized and strict electromagnetic radiation detection standard. At present, except for a few cheap products, most monitors on the market meet MPRⅡ ⅱ specification.
TCO Series Certification Swedish Professional Employees' Union (TCO) started from 1992. Based on MPRⅡ, it put forward higher requirements and stricter standards for electronic devices such as displays in terms of Ecology, Energy, Emissions and Ergonomics, and gradually evolved into the current world, including TCO' 99. Among them, TCO'92 is aimed at the display, including electromagnetic radiation, automatic power off, providing power consumption data, meeting fire prevention and electricity safety standards; TCO'95 adds the requirements for environmental protection and ergonomics on the basis of TCO'92, emphasizing the standards of low electromagnetic radiation and low magnetic field radiation, and its coverage covers displays, keyboards and system units. TCO'99 further puts forward stricter and more comprehensive standards for environmental protection and user comfort, and also puts forward specific provisions for the design of keyboards and laptops. As the fourth generation TCO certification standard, TCO'03 is stronger than TCO'99 in terms of ecology, energy, radiation and ergonomics of displays, and has become the most comprehensive and stringent certification standard for a new generation of high-quality displays in the world.
The FCC certifies that the Federal Communications Commission (FCC) is the organization that tests electromagnetic wave signals and electronic equipment. The FCC certification issued by it mainly formulates electromagnetic specifications and limits the amount of radiated noise emitted by digital equipment and switching power supplies. FCC certification is divided into two grades: A and B, and the technical requirements of Grade B are more stringent. Among them, A-class products produce strong electromagnetic waves, which will interfere with radios, televisions and other electrical appliances, so they are not suitable for home use but can be used in offices and other places; Class B products mean that the electromagnetic waves generated are relatively weak and will not interfere with signals such as microwaves, so they can be used in homes or offices, such as personal computers or telephones.
CCC Certification CCC is the abbreviation of "ChinaCompulsoryCerlification", which is a symbol of compulsory product certification recently implemented in China. At the same time, 3C certification is a combination of CCEE (Electrician), CCIB (Import and Export Quarantine) and EMC (Electromagnetic Compatibility) certification, which respectively set comprehensive standards for electricity safety, electromagnetic compatibility, radio interference and stability. All the products listed in the catalogue of compulsory product certification implemented by the state must be certified by the certification body designated by the state, obtain relevant certificates and affix certification marks before they can be sold, imported and used in business activities. 3C logo has two versions: CCC(S) and CCC (S&; & E）。 CCC(S) only passed the safety standard certification, CCC (S&; & E) indicates that the product has obtained both safety and EMC certification (as shown in Figure 2).
Understand and master the above certification standards, and you will be "aware" when purchasing "green" monitors. In fact, when purchasing, you only need to "follow the prescription" and select those products that have passed the certification of TCO'99, TCO'03 and 3C. Because these products have passed the most stringent standards such as TCO'99, they should try their best to meet the standard requirements contained in the relevant certification in every process and link of design, material, manufacturing, delivery and sales. Therefore, it is basically unnecessary for users to know the specific technical details of the product. As long as it has passed the certification such as TCO'99, it shows that the electromagnetic radiation and other hazards of the product have been minimized and it can be used safely. For example, a display that has passed TCO'95 should meet the safety standards of ISO924 1 Ergonomics and IE950 in design, widely use recyclable and nontoxic materials in materials, and meet the relevant standards in ISO series and the requirements of low electromagnetic radiation (EMI) and low magnetic field radiation (EMC) in production, manufacturing and delivery. It can be seen that the TCO standard is not only very strict, but also its test process and test scheme are extremely harsh. Therefore, the display that meets the certification standard of TCO'95 or above can meet the requirements of being a "green" display in many aspects, such as ecology, energy, radiation and ergonomics. It is a truly high-quality and high-security display, and it is certainly your wise choice. Judging from the proportion of certified displays, non-radiation and environmentally friendly TFT liquid crystal displays account for a large part. In order to prevent fraud, you can log on to the official website of TCO evaluation agency (www. TCOdevelopment.com), and all the manufacturers and brand names certified by TCO standards can be found.
At present, there are many monitors certified by TCO'99 and above on the market. Philips, LG, BenQ, acer, AOC, aigo, NESO, Meg and other big manufacturers have all launched their own excellent products.
The easiest way to judge whether the chassis has anti-electromagnetic radiation function when purchasing is to check whether it has passed the relevant anti-radiation standards certification such as EMI, FCC and 3C. At present, the typical products on the market are radiation-proof cases of Huaqi Patriot, Century Star, Jinhetian, Foxconn, Galaxy, Colorful and Tt.
When using a computer, it is necessary to adjust the brightness of the screen. Generally speaking, the greater the brightness of the screen, the stronger the electromagnetic radiation, and vice versa. However, it can't be turned too dark, so as not to affect the viewing effect because the brightness is too small, and it is easy to cause eye fatigue.
When operating the computer, pay attention to keeping a proper distance from the screen. The closer you are to the screen, the greater the electromagnetic radiation the human body receives, so it is better to be 0.5M away from the screen.
In addition, after operating the computer, many particles of electromagnetic radiation will be absorbed on the face. Wash your face with clear water in time, which will reduce the radiation exposure by more than 70%.
The location of the computer is very important. Try not to let the back of the screen face people, because the computer has the strongest radiation on the back, followed by the left and right sides, and the front of the screen has the weakest radiation. As long as you can read clearly, the distance should be at least 50 cm to 75 cm, which can reduce the harm of electromagnetic radiation.
Pay attention to indoor ventilation: scientific research has confirmed that the computer screen can produce a carcinogen called dibenzofuran bromide. Therefore, it is best to install a ventilator in the room where the computer is placed. If not, pay special attention to ventilation when surfing the Internet.
Care: The most obvious part of facial aging is the eyes, so eye care is particularly important.
Eye cream: It has moisturizing effect, besides reducing the problems of dark circles and bags under eyes, it also has the effect of improving wrinkles and fine lines.
Eye gel: The effect is similar to that of eye cream, but the gelatinous texture is more refreshing, and there is no burden when using the skin during the day. Most of them are to eliminate eye bags and dark circles and relieve eye skin symptoms.
One kind is drinking tea.
83% of people who use computers often feel tired eyes, and 64% often feel sore shoulders and low back pain. In addition, many people have symptoms such as tears, loss of appetite, sore throat, cough, chest tightness, and even slow movement and memory loss.
Computer radiation not only harms people's health, but also affects the quality and efficiency of work. For the busy people, the easiest way to resist computer radiation is to drink 2-3 cups of green tea and eat an orange every morning. Tea is rich in provitamin A, which can be quickly converted into vitamin A after being absorbed by human body. Vitamin A can not only synthesize rhodopsin, but also make eyes see things more clearly in dark light. Therefore, green tea can not only eliminate the harm of computer radiation, but also protect and improve vision. If you are not used to drinking green tea, chrysanthemum tea can also play a role in resisting computer radiation and regulating body functions.