Does The Radiation Protection Clothing Of Pregnant Women Only Play A Warm Role?

Pregnant women wear Radiation-proof clothes Can radiation really prevent radiation? What kind of radiation can you prevent from radiation? CCTV's truth show once again triggered controversy over the effectiveness of radiation protection clothing for pregnant women.

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Television experiments have been questioned.

In April 7th this year, CCTV broadcasts a program "to wear radiation proof clothing for pregnant" program, starting with the phenomenon of electromagnetic radiation of an electrostatic ion generator, and displaying the protective ability of pregnant women's radiation protection clothing through field experiments.

At the beginning of the program, the host invited the staff to pick up an ordinary fluorescent tube, and contacted with the high voltage electrostatic ion generator. Then, the host bought the radiation proof clothing on the market, and then put it on the electrostatic ion device. Then the fluorescent tube was put on. Finally, in the face of the doubt of the mass observation group, the host invited one of the observers to himself. clothes Cover the ion and then close the tube to the ion. The tube is lit again.

An academician at the scene explained that the electrostatic ion ball will emit electromagnetic radiation with very strong field strength when it is energized. Electromagnetic radiation causes the phosphor in the fluorescent tube to glow. Even if it does not energized, it can also emit light. Because of the shielding effect of the radiation protection clothing on the electromagnetic field, the second groups of experiments use radiation clothing to cover the ionic ball and the lamp tube is not bright; and the third group is due to the ordinary. clothing Shielding is not available, so the electromagnetic radiation runs out of the ordinary clothes and lights the lamp again.

However, after the broadcast, experts questioned the conclusion of the experiment. Last week, our reporter and expert repeated verification, the results were unexpected.

　 Reveal secrets

Why do ionic balls light fluorescent lamps?

In CCTV's program demonstration, the host holds a fluorescent tube, and the fluorescent tube lights up when approaching the ionic ball. Reporter verification also found that the hand-held fluorescent tube, closer to the "ion ball", the brighter fluorescent tube.

For this reason, Yang Xin Village, senior engineer of East China Electric Power Research and test institute, explained that no matter what fluorescent tubes, mercury inside the glass tube is filled with micro pressure. Mercury vapor will generate ultraviolet light when stimulated by electric field, and then stimulate phosphor emission. When used normally, the filament at both ends of the ordinary fluorescent tube is heated to accelerate the volatilization of mercury. Only 220 volts of voltage can be lit with the help of the starter and used for lighting. The local area near the ion sphere first glimmering and then expanded to the entire tube. This physical phenomenon can also be observed in other occasions near high voltage sources, such as under the ultra high voltage power line.

In the demonstration of the "ionic ball experiment" of CCTV program, another important experiment is that when the host puts the radiation protective clothing on the electrostatic ion sphere, then the fluorescent tube is close to the ionic ball, but the fluorescent lamp does not light up.

How does the fluorescent tube not cover the glass ball? Is it really shielding the pregnant women? Under the guidance of the experts, the reporter repeated the experiment, covered the glass ball with the radiation proof pregnant clothing, and then put the end of the fluorescent tube close to the ionic ball.

The reporter found that the fluorescent tube was lit up at about 40 centimeters near the ion sphere. Not only that, experts have changed the use of three kinds of radiation proof pregnant women bought from supermarkets to cover glass balls, and the fluorescent lamps are brighter than those without shielding clothing.

Is it the protective clothing that volunteers buy has no shielding effect?

Yang explains that this is not the case. The radiation protection maternity dress itself is woven with a metal net covering the surface of the ionic ball glass, just like a whole piece of electrode plate, so that the discharge in the glass ball is enhanced, thus raising the surface potential to the surface of the sphere, and enhancing the surrounding electric field. Therefore, fluorescent lamps are not brighter, but brighter.

　 find

The reporter was shocked by the experiment.

In the experiment, the reporter accidentally touched the radiation proof maternity clothes on the surface of the ionic ball, and felt that the fingertips were instantly struck by electric shocks. Pregnant women radiation suits actually charged?

Yang Xin Cun reminds the reporter: "never touch the ion ball." Maternity Dress 。 Because a large area of pregnant women will gather considerable discharge current, touching with hand will cause the current to flow through the body instantly, causing discharge pain and obvious cracking noise.

So what's wrong with CCTV? Experts continue to use experiments to reveal why.

Yang Xin Cun takes out a metal wire to instruct the reporter to connect the wires to the metal fence on the windowsill, and the other side touches the pregnant women's radiation protection clothing on the ionic ball.

"Thorn -" the conductor in the reporter just touched the radiation protection clothing. clothes A long string of sparks on the surface frightened the reporter. At this time, Professor Yang's fluorescent lamp was extinguished immediately. When the reporter took the wiring out, the fluorescent tube was shining again.

Yang Xin Cun explained that the conductor played the role of grounding. It can be deduced that pregnant women's radiation protection clothing on CCTV programs can be grounded through items such as tables. "Because the surface of the ion sphere is grounded, the external electric field decreases, so that the fluorescent tube is extinguished. Therefore, it is not the role of pregnant women in the so-called radiation shielding.

Subsequently, the experts also showed to reporters that, regardless of any method, as long as the surface of the ionic ball is grounded, the fluorescent tube can be extinguished. For example, in the experiment, the reporter pressed a hand on the surface of the glass ball according to the requirements, and the fluorescent tube was extinguished. Experts explained that this is to allow the surface of the ionized sphere to be grounded through the human body, because the body is low resistance, which can be seen as a partial grounding of the contact point and releasing its surface charge.

At last, Yang Xin Cun pointed out that without distinguishing the existence of low frequency electric field, magnetic field or radiofrequency electromagnetic field around the ion sphere, the "intuitive fact" that only illuminated the fluorescent tube is used to prove that the radiation protection effect of radiation protection clothing is neither scientific nor rigorous. This "popular science design" will mislead the public. {page_break}

　 dispute

Is radiation protection clothing necessary for pregnant women?

Reporters later on some supermarkets in Beijing to understand the sale of radiation protection clothing for pregnant women. In a supermarket in the East Fourth Ring Road, the reporter saw the pregnant women's radiation protection clothing and baby products displayed at the same time.

A shopping guide was skillfully prepared to wrap the cell phone in a belly pocket and demonstrate the shielding effect to reporters.

"Silver fiber is a new technology, patented technology, the most popular." After the shopping guide demonstration was completed, a price tag of 700 yuan skirt radiation protection clothing for pregnant women was presented to reporters. Seeing reporters seemed interested, shopping guide also picked out a small plastic bag on the clothes board, which contained a small piece of radiation protection product distribution. cloth 。 Shopping guide said: "cloth head can use fire point, after burning, the remaining metal mesh, this is the mesh of radiation resistant metal wire."

In the volunteers, three pregnant women's radiation protection clothing purchased at random from the experiment, a silver grey vest with a price tag of 760 yuan, a brand "electromagnetic wave protective belly pocket" priced at 158 yuan, and a common radiation protection clothing priced at 118 yuan were selected.

According to the specification of radiation proof clothing priced at 118 yuan, the metal fiber content is 30%, cotton 50% and polyester 20%. According to the instructions, the radiation protection clothing is tested at frequencies between 10 MHz and 3000 MHz, and the test results are over 99.999% of shielding power through fabric electromagnetic wave energy.

In a well-known anti radiation clothing official website, the reporter noted that the website claims that the fetus with a weight of 1kg is 50 times more severely damaged than the adults with 50kg weight. At the early stage of pregnancy, the fetus is less than 1kg, and the radiation is more harmful. "

Reporters noted that in the CCTV program, in order to confirm the "effective" of the radiation protection clothing for pregnant women, besides the demonstration of ionic ball, there were many tests in the program, including the contrast test before the microwave oven and the contrast test of the single high frequency antenna, emphasizing the fact that the radiation proof pregnant clothing can reduce the high frequency electromagnetic field.

However, experts pointed out that the logic error is: "radiation proof pregnant clothing can attenuate high frequency electromagnetic fields" and can not deduce that "pregnant women wear radiation protection clothing is really necessary" conclusion.

Yang Xin Cun pointed out that a large number of metal wire knitted fabric can effectively attenuate radio frequency (RF) electromagnetic field, which is beyond doubt. However, the lowering effect of pregnant women's clothing is only limited to megahertz electromagnetic waves. At the same time, there is no evidence that the electromagnetic waves of megahertz can cause more radiation than pregnant women.

"Another analogy is that hypotensive drugs can also play a certain antihypertensive effect for normal people without hypertension, but we all know that you do not need to take antihypertensive drugs. This is the same as whether the pregnant woman needs to wear radiation proof clothing. Yang Xin Village stressed that the test of the percentage of pregnant women's radiation suits "can attenuate the percentage" does not prove that they are effective for the health of pregnant women or fetuses. In the accurate public science popularization, the effectiveness of certain protective measures must be reflected in whether the measure is effective in eliminating or reducing certain hazards.

expert

Avoid misunderstandings in business promotion

According to Dahl, who is a non-governmental environmental protection organization, asked for hundreds of unpaid electromagnetic field testing data for the public in Beijing in the past 3 years, the strength of an electric utility facility has not yet been measured.

"Radiation proof clothing is not necessary to wear in normal living conditions." Dahl asked the director of environmental testing He Xiaoxia's point of view very clear.

He Xiaoxia will provide unpaid electromagnetic environment quality testing to the citizens of Beijing almost every week. "Since 2009, there have been no 1 cases exceeding the standard. The greatest achievement of detection is actually the public's peace of mind.

"The prevalence of radiation protection clothing for pregnant women is, on the one hand, misleading by businessmen, and on the other hand, the public is overly concerned about the pollution of the electromagnetic environment." He Xiaoxia thinks.

Yang Xin Village quoted the speech of a member of the CCTV program, "the electromagnetic environment in the living environment is safe". The view is: "WHO and the international non ionizing radiation protection committee (ICNIRP) are clear: the" public exposure limit "in the international exposure standard is safe for special populations including pregnant women.

Statistics show that the 2010 guideline of the international non ionizing radiation protection committee defines the term "public" as "public exposure" as follows: "public" means the whole population. It includes people of all ages and different health conditions, including specific groups or individuals, such as the weak, the elderly, pregnant women, infants and young children.

"There is no real health problem," Yang stressed once again. WHO has made clear that in the environment, the extremely low frequency field exists in the form of "electric field" and "magnetic field". The lower frequency electromagnetic wave is defined as "electromagnetic field", and the electromagnetic wave of non high frequency can be called "electromagnetic radiation". He said that it is inappropriate to introduce the concept of electromagnetic radiation into the health field of electromagnetic fields.

Facing the industrial chain and huge commercial interests behind the radiation protection clothing for pregnant women, Yang Xin Cun smiled and said, "I will not oppose the public purchase, at least it can play a role of psychological comfort or warmth."