88

FAQ

Leave blank for all. Otherwise, the first selected term will be the default instead of "Any".

Cellular Antennas

Are there recommendations regarding living near a cellular base station?

Cellular base stations installed in residential areas are controlled by permits for installation and operation, issued by the Ministry of Environmental Protection.  These permits are issued in accordance with the recommendations of the Ministry of Environmental Protection and the Ministry of Health regarding exposure to radiation from cellular antennas.  The recommendations in Israel are more stringent than the international recommendations, and stipulate that the exposure to radiation from base stations, in areas where the public may be chronically exposed, must not exceed 1/10th of the recommended level determined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP)In areas where the public may spend a shorter amount of time the exposure permitted is 30% of the ICNIRP recommendations.

 

Surveys to assess the energy level in proximity to locations of cellular base stations in typical urban areas showed that at a distance of 50 m from the cellular base station, radiation usually drops to a few microwatts per cm2.  Adverse health effects of exposure to such low levels have not been established to date.

Cellular base station in residential area

Cellular base station in residential area

 

In any case, one can verify that exposure to non-ionizing radiation does not exceed the values set in the table in the Ministry of Environmental Protection's document (Hebrew), which summarizes the maximal exposure levels allowed for radiofrequency radiation.

 

22.10.2015

How can one measure radiation from a cellular Antenna independently?

Anyone wishing to perform private measurements of radiation may do so, by summoning a professional radiation surveyor.  The Ministry of Environmental Protection publishes a list of persons authorized to perform radiation measurements, as well as a list of suppliers of measuring instruments.

 

Dosimeter - radiation measurement instrument

Dosimeter - radiation measurement instrument

 

22.10.2015
What is the minimal distance allowed between a cellular base station antenna and a residential area?

The minimal distance between a cellular base station antenna and a residential area depends on various factors, and is determined according to intensity of emission, direction, height of the base station antenna, and other technical considerations.  Safety ranges change according to communications coverage in an area, which depends on the density of users in the given area.  This distance is authorized by the Ministry of Environmental Protection in accordance with the Non-Ionizing Radiation Law.

 

A cellular base station antenna  with symbolic radiation

A cellular base station antenna 
with symbolic radiation

 

For each station there is a minimal distance stipulated in the permit, at the front of the antenna in the direction of emission (horizontal minimal distance), as well as a vertical distance.  This means that the public is prohibited from entering the area within a distance shorter than the minimum allowed by the permit.

 

22.10.2015

Children

Are there special guidelines regarding the use of radiation-emitting devices by children?

In general, the guidelines of the TNUDA center and the Ministry of Health regarding radiation-emitting devices are based on the precautionary principle, which aims to strike a balance between the developing technological needs of modern society and the degree of caution required to safeguard health.  The principal recommendation for reducing the level of radiation to the user is to place the source of radiation away from the body (for instance, by using earphones when talking on a mobile phone).

For children, it is recommended to follow strictly the general recommendations regarding the use of mobile phones, because children are more sensitive to developing illness following exposure to harmful agents.  This sensitivity is due to a number of factors:

  • Body tissues of children are developing, hence they are more sensitive to environmental hazards.

  • Children's life expectancy is long, so that they may accumulate significant amounts of exposure.This long life expectancy makes them vulnerable to developing diseases that manifest themselves several years after exposure (such as cancer, which may develop some 10-40 years or more after exposure to the harmful agent).

  • Exposure of children to radiation touches on ethical issues related to decision-making on behalf of minors.

In general, it is known that the degree of sensitivity of children to carcinogenic agents is inversely related to age: in other words, the younger the child, the greater the risk.

It should be mentioned that many parents allow their children, even babies, to use non-ionizing radiation-emitting devices, such as Tablets.  Even if the amount of radiation emitted by such devices is low, the use of non-ionizing radiation-emitting devices by children should be given due consideration in view of the above points.

 

22.10.2015

Health effects

Are there studies showing a link between non-ionizing radiation and developing disease?

There is no unequivocal answer to the question of whether non-ionizing radiation (such as that emitted by mobile phones, household cordless phones, wireless communications networks, cellular base stations and the electric power grid) can endanger health or cause disease.  Scientists are divided in their opinions on the topic.

 

Most studies on radiofrequency emissions have focused on the development of different types of cancer, especially brain tumors, acoustic nerve tumors and salivary gland malignancies.  Other health outcomes studied were the effects on fertility (e.g. sperm morphology and motility); on brain function (e.g. cognitive function, attention and concentration deficit disorders in children, brain development in babies); on the heart and circulatory system (blood pressure and heart rate); on hearing, saliva (secretion, composition and flow), fat profile of blood, obesity, development of multiple sclerosis, neurodegenerative diseases such as Alzheimer's, headaches, and the 'non-ionizing radiation hypersensitivity' syndrome.

 

In 2011 a Working Group of the International Association for Research on Cancer (IARC) stated that there was limited evidence of an increased risk of developing malignant brain tumors (glioma) and benign acoustic nerve tumors among mobile phone users.  The Working Group also pointed out that the results of current studies were insufficient for drawing clear conclusions about other types of cancer and/or about occupational or environmental exposure.  Based on this conclusion, they classified radiation from radio waves, such as from mobile phones, in Category 2B in the list of carcinogens, thus defining radiofrequency emissions as possibly carcinogenic to humans.

 

Studies on electric power grids (extremely low frequency, ELF) also focused on the risk of developing cancer, especially leukemia in children; effects on pregnancy outcomes (miscarriages and birth weight); effects on children's behavior, on cognitive function, hormones, neurodegenerative diseases (e.g. Alzheimer's) and heart diseases.

 

Population studies have pointed to an increased risk of developing leukemia (a blood cancer) among children who lived in close proximity to high tension wires, compared with children who lived further away.  Here too, as for non-ionizing radiation from radiofrequency waves, no unequivocal causal effect between exposure and morbidity has been proven.  However, on the basis of these studies the IARC classified non-ionizing radiation at lowest frequencies as 'possibly carcinogenic to humans' (category 2B).  To date no link between radiation from the electric power grid and other types of cancer has been established conclusively, neither in children nor in adults.

 

22.10.2015

 

 

 

 

 

 

 

Magnetic & electric fields of low frequencies (ELF)

Do powerline adapters emit stronger or weaker radiation than Wi-Fi (routers and access points)?

Powerline network adapters (working via the electricity network) use information modulation technology (modulation, information construction) on infrastructure wires for transmitting internet communications over short ranges over the home electrical infrastructure.

The modulation is done over a wide range of frequencies, determined by the rate of data transmission and from which the radiation frequencies which could develop during data transmission was determined.

Network adapters utilize two end units, one for receiving the information from the router and data modulation over the electrical infrastructure wires, and another for receiving it in another location.

The radiation levels produced by this technology are very low, because the signals passed through the electricity wires (in house walls) are relatively weak, and because rather than the radiation being produced by a broadcasting antenna (as exists in Wi-Fi technologies), it develops in a “parasitic” manner in the vicinity of the electricity wiring in house walls or in the vicinity of electricity sockets (and the adapters themselves), that do not act as efficient antennae.

Various measurements made for internet powerline network adapters, have shown levels of radiation below one nano-watt (one billionth of a watt) per cm2 at a distance of 1 meter from the electrical wiring – less than one thousandth of the radiation levels produced at a distance of 1 meter from a wireless routers and access points.

It should be noted that there are powerline network adapters that also use wireless technology (for making a wireless connection for cellphones, tablets and computers in the target area), and in these cases they also produce radiation at the 2.45 and 5 GHz frequencies (like the radiation from Wi-Fi networks).

 

To what degree does exposure to electromagnetic radiation increase when the electrical panel is located inside the house?

Levels of exposure to magnetic fields in the vicinity of electrical panels are mainly dependent on the size of electric currents and the way the conductors are arranged inside the panels. Distance from electrical panels also has a large effect.

The overall value of electrical currents developing inside home electrical panels can reach tens of amperes, as a function of the type of consumer connection to the electric company and the degree of electricity consumption. Exposure levels in the vicinity of the panels may reach several tens of milligauss and even more than this. However, as the distance from the electrical panels increases, exposure levels drop sharply.

 

The recommended method of reducing exposures to magnetic fields from electrical panels, according to the precautionary principle, is by keeping sufficient distance from the electricity cupboard. Thus, at a distance of 1 meter from the electrical panel, exposure levels drop to a few milligauss. In addition, the location of the electrical cupboard should not be in the walls of residential rooms (in which people may spend prolonged time periods).

What kind of radiation is emitted by hybrid cars?

The hybrid car, as its name implies, combines propulsion based upon energy from traditional fuel and from electric energy that accumulates during motion. Electric currents used in the electric part of propulsion while driving create a surrounding of low frequency magnetic fields. This radiation is defined as non-ionizing radiation from the electricity grid in the Extremely Low Frequency radiation range (ELF).

The Ministry of Environmental Protection and Health Ministry recommendations on the maximal radiation exposure level permissible from electrical appliances are available in the article on electric grids.

The power of magnetic fields created in hybrid cars differs from car to car according to the automobile make and model, and there are even differences between different cars from the same manufacturer and the same model. Also, the distribution of the power of the fields, in the car’s interior, varies from place to place within the car.

At present there are different positions regarding levels of magnetic fields created by hybrid cars and their radiation hazards. Also, the scientific knowledge existing on this subject is limited and there are no clear guidelines regarding their use.

In Israel, the issue of hybrid cars was addressed at length by the Ministry of Environmental Protection which authorized their use. The Ministry conducted extensive tests to examine the exposure to non-ionizing radiation inside hybrid cars and inside regular cars.

A link to data on radiation exposure in hybrid cars (Hebrew) in Israel may be viewed, detailing the average yearly level of exposure in each seat in the various cars checked, according to a stringent assumption of 18 hours average weekly time spent in the car.

What radiation is emitted from a server room?

Relatively low strength electrical currents and voltages exist in servers and therefore the non-ionizing radiation in their vicinity is at a very low level (servers are not a special source of radiation, that is, the radiation is not generated by transmitters and antennae intentionally, but rather exists as a by-product).

There are magnetic fields on the electricity grid frequency in the vicinity of power sources that use servers. However, at a distance of one meter or more from them, the field level is mostly below the level of a few milliGauss, and complies with the Ministry of Health and Ministry of Environmental Protection recommendations for maximal permitted level of exposure to magnetic fields from electrical appliances. 

What is the minimal distance allowed between electrical installations (such as power lines or transformers) and residential homes?

The Ministry of Environmental Protection determines the criteria for distances separating electrical installations from sensitive land use sites such as residences, educational institutions, etc. These criteria depend on a large number of factors, such as the type of installation, the electricity that flows through it, the distance and height of the land use site, relative to the wires through which the electricity flows, the layout of the wires, etc.  The Ministry of Environmental Protection website lists the criteria for determining distances between electrical installations and residences, for each type of installation (Hebrew). 

 

Recommendations of the Ministry of Environmental Protection and the Ministry of Health regarding the maximal allowed level of radiation from electrical installations are:

  • 2000 milligauss for short-term exposure (momentary exposure)

  • 4 milligauss daily average for the busiest day (continuous prolonged exposure).

Chronic exposure, or continuous prolonged exposure, is defined as exposure of more than 4 hours daily for more than 5 days a week.  Residences, offices, educational institutions, commercial and industrial buildings, etc., are considered locations of chronic exposure.

 

For precise data on radiation levels, an authorized radiation surveyor may be summoned, from the list of authorized surveyors on the Ministry of Environmental Protection's website (Hebrew). 


 
 26.10.15

Mobile phones

Do cellphones emit more radiation inside cars?

As a rule, cellphones increase the strength of their emissions when there are poor reception conditions, with corresponding increase in the level of radiation exposure in their vicinity.

 

Radiation exposure levels from cellphone use inside cars are higher than from use outside cars in open areas, but the difference is not great. This is because of the relatively small effect of cars’ structures on reception conditions inside them.

 

The reason for this is that because cars have a relatively large area of windows, which do not constitute a meaningful obstacle for radiation. Also, cellphones are usually located next to windows and their use in cars is usually via a hands-off speaker, which also has the advantage of distancing the phone from the user’s body thus significantly reducing the level of exposure.

 

It is noted that there is reflection of radiation from the car walls and from other metal objects inside the car, but their contribution to an increase in radiation levels is not great, because of the presence of plastic and upholstery and because of radiation dispersion and absorption effects.

 

12.3.2018 
Is there a difference in terms of radiation exposure between using text messages and talking on cellphones?

One of the recommended ways of reducing exposure to radiation when using a cellphone, is to use text messages (and not talking).

Sending a WhatsApp message (using words) involves sending information and transmission during a relatively short time than a cellphone conversation, and also involves distancing the cellphone further from the head and the body than does a cellphone conversation, and as a result there is significant reduction in the degree of radiation exposure.

How can one reduce the levels of radiation exposure while using mobile phones?

The easiest way to reduce the level of radiation exposure is by holding the phone away from the body!

 

In general, the guidelines issued by the TNUDA center and the Ministry of Health are based on the precautionary principle, while maintaining a balance between the technological needs of the society in Israel and the degree of caution required to safeguard health.  The main recommendations are:

  • Using a loudspeaker/personal hands-free accessory or earphones (not wireless) or any other device that keeps phone away from the body while talking.

  • Restricting talking in locations where reception is weak (where base station are relatively scarce or reception is screened off, as in elevators or trains).

 
22.10.2015
Is it safe to use a hands-free accessory for the mobile phone while driving?

This question refers to two different issues: "Does using the accessory pose a health hazard through the radiation emitted from the phone?" and "Does using the accessory while driving increase the risk of accidents resulting from the driver's diminished concentration?"  Regarding protection from radiation, using a hands-free accessory is preferable to holding the phone next to the head.  On the other hand, as to the safety of driving, it appears that the use of such an accessory also poses a real risk.  Recent studies have shown that the degree of distraction resulting from phoning while driving, whether using a hands-free accessory or earphones, is similar to that when using the phone placed next to the ear.  This inattention may substantially increase the risk of accidents so that on the whole it is recommended to refrain from talking on the phone while driving. 

 

Studies have shown that the effect of a phone conversation on the driver's behavior is similar to or even greater than that due to driving under the influence of alcohol.  Even more dangerous situations occur when the driver's sight is diverted from the road to the phone, as when tapping a number on the phone or answering a text message.  Such activities should be avoided altogether.  It must be emphasized that young drivers, for whom driving is not yet a sufficiently automatic activity, are most influenced by diversion of attention through using a phone while driving.

 

22.10.2015
Is it safe to use a mobile phone in elevators?

Elevators are usually built of metal that does not allow radiofrequency waves from the phone to be transmitted outside the elevator to the antenna/base station that receives them.  Consequently, the phone 'strains' to contact the external network while emitting its highest level of radiation.  In addition, a phone conversation cannot usually be conducted normally and the user will experience reception problems.  The screening off of radio waves in the elevator exposes the user to the highest level of radiation from the phone.  It is important to note that in such a situation persons in the elevator may be passively exposed.  It is thus recommended to refrain from using mobile phones while in elevators (usually a short period of time) and to postpone the call until after leaving the elevator.

22.10.2015

Radiation Measurements

How can radiation be measured?

In Israel, a reliable test of the electromagnetic radiation level can be performed via a certified surveyor from the Ministry of Environmental Protection.

The Ministry of Environmental Protection website publishes a list of individuals certified to perform radiation tests (Hebrew).

You can read about non-ionizing radiation measurements in an article by Dr Amnon Duvdevani (Hebrew), specialist of non-ionizing radiation hazards, on the Israel Institute for Occupational Safety and Hygiene website.

Is there a guideline regularizing the frequency of radiation measurements in schools?

The Ministry of Education instructs the local authorities to supervise interior sources of radiation by general directive statements. The Environmental Protection Ministry is responsible for overseeing external radiation sources, according to the non- ionizing radiation law.

An Education Ministry General Director Statement from 2013 (“use of communication equipment and end-user devices in schools – health and safety effects”) published guidelines regarding radiation measurements in schools. According to the directive: “in every school where communication equipment and end-user devices are installed RF and ELF radiation measurements must be performed by a qualified person prior to and after installation, and to ensure that radiation levels meet the Environmental Protection Ministry requirements. The measurements must be performed when the equipment is activated all over the school.”

The Education Ministry Environmental Safety Department has updated that radiofrequency (RF) and Extremely Low Frequency (ELF) radiation measurements are performed during installation and whenever there is a change in the network and in the extent of the equipment and end-user devices.

For more on the subject of ELF radiation measurement see Exposure to radiation from the electric grid in schools.

Radiation-Emitting Household Appliances

Is there any risk associated with metal detector checks?

Metal detectors are designed specifically to detect metal objects at close range. Metal detectors use magnetic fields of very low frequency and weak strength. These fields are within the non-ionizing part of the electromagnetic spectrum; low frequency radiation that cannot cause any change to the structure of materials through ionization (distancing an electron from an atom), as opposed to ionizing radiation (for example X-rays and gamma rays).

 

The operating mechanism of hand held metal detectors is based upon active detection – producing an alternating magnetic field at very low frequencies, by a coil, and detection of changes in the magnetic field close to the detector as a result of the presence of metallic objects, using a coil (usually a different coil is used for detection). When metallic objects are present, the alternating magnetic field acting on them causes electrical currents to flow in them and creates secondary magnetic fields that are detected by the metal detectors and trigger an alert.

 

The strength of the magnetic fields created by metal detectors is relatively low, so the exposure of people being checked to magnetic fields meets international standards.

 

Regarding health effects, the exposure to magnetic fields as a result of metal detector use is at a low level compared to permissible levels, and therefore there is no acute effect at these frequencies (neural or muscular excitation). Regarding long term effects, there is little information in the scientific literature about prolonged (“chronic”) effects of the intermediate frequency (IF) range, to which metal detectors belong. In addition, it should be noted that exposures are very brief during the scan and there is not extended exposure.

 

That said, it is generally accepted that people with cardiac pacemakers or other implanted medical devices should take care regarding use of metal detectors. Guidelines and regulations do not include any stricter limitations on magnetic field exposure for pregnant women than for others. There are countries and organizations that allow pregnant women to undergo separate checks.

 

12.3.2018
Does radiation from Wi-Fi network pass through walls?

Overall, radiation does penetrate walls, but this radiation is weakened as a function of the type of wall and the presence of openings such as doors etc. (namely the radiation measured on the other side of the wall and passing through it, will generally be up to tens of times weaker than that measured in the room where the router is located). This is also true for wireless routers and for cellphone radiation, which uses Wi-Fi or cellular networks.

In accordance with the precautionary principle, the most important rule for limiting exposure to non-ionizing radiation is to distance the radiation source from the body, since radiation drops significantly as the distance from the radiation source grows. Therefore, moving a wireless router to another room and using a cellphone in another room achieve the advantage of reducing the level of radiation relative to the adjacent room, both by increasing the distance and by the blockage created by the wall material.

The cumulative effect of these reductions usually leads to the radiation level in the adjacent room being thousands to hundreds of orders of magnitudes lower than in the room where the sources are located (the wireless router or cellphone).

What is the level of radiation exposure from using internet based television?

Television using a home Wi-Fi network, serves as a “consumer” of this network. Because the broadcasted information uses relatively big files (video files), it often causes the wireless router to operate at its maximal capacity. Nevertheless, it should be clarified that even under these circumstances, the level of radiation exposure from the router is relatively low. For example, at a distance of 1 meter from the wireless router operating at full capacity, the exposure level is about 1 microWatt per cm2. This level of exposure is 1/1000 of the maximal exposure level set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and about 1/100 of the recommended levels of prolonged exposure set by the Ministry of Environmental Protection. When the distance from the router is greater, the radiation level decreases with the distance squared (doubling of the distance leads to a 4 fold decrease in radiation level etc.)

 

Are there recommendations regarding the use and placement of electromagnetic radiation-emitting devices during sleep?

The level of exposure to non-ionizing radiation decreases significantly with the distance between the human body and the source of radiation.  Therefore, it is recommended not to place radiation-emitting devices that have a fixed location (such as routers, mobile phone chargers, supports for cordless phones) in rooms where one spends many hours, such as bedrooms.  If there are electrical and other appliances in the bedroom (such as TV, computer, adjustable bed) they should be placed as far as possible from the bed and/or switched off /disconnected during sleep.

 

 25.10.15
Are there recommendations for use of nail dryers?

Most nail dryers are based on bulbs emitting ultraviolet radiation (UV-A). Some drying devices are based on LED bulbs.

מכשיר לייבוש ציפורניים

Nail Dryer Device

 

UV bulb -based nail dryers

In general exposure to ultraviolet radiation emitted from the sun or from an artificial source might cause advanced skin aging, wrinkles, development of cataracts, and conjunctival damage. A significant health hazard of exposure to this type of radiation is developing various types of skin tumors, including malignant melanoma. Acute exposure to this radiation may cause burns.

Studies have shown that UV bulbs in nail dryers emit mainly UV-A radiation (it is possible that they also emit UV-B and UV-C radiation, but in tiny amounts that cannot be measured).

The ultraviolet radiation emitted from nail dryers depends on the type of device, type of light source, bulb power and number of bulbs in the device. It has been found that the greater the bulb power, the higher the level of radiation emitted by the device.

From scientific finding currently available it appears that exposure to radiation from UV bulbs for nail drying does not significantly increase the risk of skin cancer in the hands throughout life, apart from the effect of cumulative exposure. And therefore the greater the exposure, the risk of skin damage increases. It is recommended to reduce exposure as much as possible.

The risk of exposure may be reduced significantly by wearing fingerless gloves or by applying sunscreen to the hands before exposure.

LED bulb -based nail dryers

These bulbs also emit UV radiation, but in a narrower spectrum and with higher energy concentration than UV bulbs. To the best of our knowledge, LED bulbs used for nail drying do not emit significant UV-B and UV-C radiation or shorter wavelength radiation.

Are there recommendations regarding the use of Wi-Fi networks in private homes?

In general, the level of radiation measured during the use of Wi-Fi is low.  The maximal transmission output of a typical cordless home router is about 100 milli-watts, and at a distance of 1 meter from it the level is only about 1 micro-watts/cm2.  This level is only 1% of the recommended threshold in Israel for exposure to transmission at the recognized frequency for the Wi-Fi network.  Modern forms of routers and mobile phones emit levels lower than this, and may drop to a level of 20 milli-watts.

 

When using laptops or mobile phones connected to the Wi-Fi network, the individual exposure to radiation emitted by the device is greater, because of its proximity to the body: at a distance of 30 cm the maximal exposure is about 9 micro-watts/cm2.  This is an exposure additional to that emitted by the cordless router.  In general, the recommended threshold value for exposure to any source of transmission at Wi-Fi frequency is 100 micro-watts/cm2, in accordance with the recommendations of the Ministry of Health and the Ministry of Environmental Protection.

 

As mentioned under placement of devices during sleep, it is best not to place the cordless router in the bedroom near the bed, or in any room where one spends many hours consecutively near the device.  It is also possible to disconnect the transmission from the router while the Wi-Fi network is not in use, such as at night.


 

 

 

26.10.2015

What level of radiation is emitted by a tablet?

There are two types of tablet – those that work via the cellular network and those that use Wi-Fi communication. Tablets with a modem for surfing the cellular network emit radiation with similar power levels as smartphones. Whereas those that work via Wi-Fi emit radiation with power levels similar to a Wi-Fi network.

 

When a tablet is operating on a Wi-Fi network, the level of radiation measured as a result of Wi-Fi use is low. The maximal transmission intensity of a typical home wireless router is about 100 milliWatts. Novel router devices and cellphones and advanced tablets produce smaller intensities than this and may even go as low as values of 20 milliWatts.

The level of radiation emanating from Wi-Fi sources, for example a typical home wireless router or tablet falls within the threshold requirements recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) for exposure to radiation of Wi-Fi networks.

 

According to the precautionary principle, the most important rule for limiting exposure to non-ionizing radiation is distancing the radiation source from the body – thus, the more the distance from the radiation source increases, radiation drops significantly. Therefore the tablet should be distanced from the body as much as possible.

When the internet is not being used, Wi-Fi communication can be turned off by cancelling the Wi-Fi connection or by turning off the cellular network surfing modem. Another option is by enabling “flight mode”, in which no transmission and reception are available and thus exposure to RF radiation is prevented.

 

It should be noted that since these devices are electronically operated, electrical activity occurs in their electronic systems creates very low power electricity flow. The magnetic and electrical fields and the radiation created by them are in very small levels.

At home, is it preferable to use a cordless phone rather than a mobile phone? Does the cordless phone emit more radiation when not resting on its support?

The home cordless phone transmits signals to its base in order to route a conversation outwards, thus emitting non-ionizing radiation.  In general, cordless phones have a significantly lower output than that of mobile phones.  Since the distance between the phone and its support is relatively small, there is no need for a high intensity of transmission, and the level of radiation is consequently low.

 

When the handset is not placed in its base and not in call mode, the emitted radiofrequency radiation is relatively low (compared to during a conversation). There are some models where the transmitters are switched off during the non-call mode, thus not emitting any radiation until a call is initiated.

 

When the phone is placed in its base, the radiofrequency communication channel is usually disconnected and therefore does not emit any radiofrequency radiation, but there are some devices that do not disconnect the communication channel in this mode.

 

It may thus be concluded that in general, the level of radiation emitted by cordless phones is lower than that from mobile phones.

 

It should be noted that the newer cellular networks adapt the emitted radiation to the location of the device and to the technological profile of the network.  Therefore, the mobile phone may adapt the intensity to the lowest possible level of radiation, so that the radiation emitted by the mobile phone may in fact be lower than that of the home cordless phone.

 

 

 26.10.15

 

Is radiation emitted by cellphones and wireless routers (Wi-Fi) increased in residential secure spaces?

The walls of residential secure spaces are constructed from concrete.

The main effect of the concrete walls compared to block and plaster walls, is greater attenuation (blocking) of radiation. Because of this, radiation entry into residential secure spaces is blocked to a greater degree, causing weakened reception inside these rooms – including the reception of radio transmissions, cellular base stations, routers, Wi-Fi etc.

This weak reception might increase the exposure to radiation emitted from cellphones and devices using Wi-Fi, which increase their strength (or transmit for a prolonged time) in order to overcome the reception difficulty. This is similar to the way cell phones increase their strength when they are at a long distance from cellular base stations and their reception is weak.

The degree to which reception is impaired depends on many factors, including the existence of apertures (windows and doors), the distance from the cellular site and from the wireless router in the house etc.

Similarly, there is also greater attenuation (blockage) of radiation transfer from the residential secure spaces outside (transmissions) and impaired cell phones communication inside these rooms, Wi-Fi communication etc.

It is important to note that radiation is attenuated (blocked) by concrete walls, but it does not accumulate or become trapped inside the secure spaces or inside the walls, even if there are several radiation sources (cell phones, Wi-Fi routers etc.) inside these rooms . In this manner residential secure spaces are similar to ordinary rooms whose walls are made of building blocks or plaster.

Is there a risk of exposure to radiation from the home desktop computer?

The desktop computer is a source of two types of non-ionizing radiation exposure:

  1. Extremely low frequency (ELF) emitted from the computer as an electric device.
  2. Radiofrequency radiation (RF) emitted from the wireless router when the computer is connected to a WiFi network.

Both types of radiation – ELF from the electric grid and RF from the wireless router have been classified by the World Health Organization as possibly carcinogenic to humans (category 2B).

 

Radiation from the electric grid:

Electricity is supplied to a desktop computer through the power supply from the electric grid. The computer board and the computer's various components operate by a direct current at low voltage. The computer's transformer converts the high electric voltage from the electric grid to low voltage. The electric currents of the transformer create a relatively strong magnetic field, usually a few tens of milligauss, in its close vicinity (a few tens of centimeters up to one meter). The magnetic field intensity decreases rapidly with distance, to a background level of the typical magnetic field in the home (in an average home the level of exposure is about 1 milligauss).

 

It is recommended that the user should be situated at least 50 cm from the computer's power supply.

 

Regarding RF radiation from the wireless router, the answer can be found under "Are there recommendations relating to the use of Wi-Fi networks in private homes?"

 

 30.3.16
How can a microwave oven be used safely?

 

Microwave ovens heat and cook food by microwave radiation that causes food molecules, and especially water molecules, to rotate thereby generating heat. When the microwave oven's door is closed, the oven's chamber becomes a Faraday cage (a closed chamber that is impenetrable to electric fields, named after the physicist Michael Faraday). The microwave oven door is made of glass but is shielded by an iron screen, preventing radiation from escaping the closed chamber.

 

As long as the microwave oven is undamaged, that is, the microwave oven door is sealed, closes correctly and there are no holes in the door's screen, it is safe to use the oven and remain in its vicinity.

 

If there is concern that the microwave oven is faulty. For example, if the door is not sealed, there is a hole in the door's iron screen or in the oven's chamber, it is recommended not to use it.

 

When the microwave oven is operating it is recommended, as a safety precaution, to be at a distance of 50-100 cm from it.

 

A Ministry of Environmental Protection-authorized radiofrequency inspector can check the intactness of the microwave oven. For your convenience a list of approved inspectors for conducting measurements of non-ionizing radiation may be found in the following link: http://www.sviva.gov.il/subjectsEnv/Radiation/measurements/Pages/default.aspx

8.6.16

 

Do underfloor heating systems cause exposure to non-ionizing radiation?

Underfloor heating consists of an electric wire grid that is installed under the floor tiles. An electric current passing through the wires, heats them and the heat is transferred to the floor thereby warming the room.

Underfloor electric heating systems

Underfloor electric heating systems

 

Single wire element underfloor heating was manufactured and sold in Israel until a few years ago. In this type of underfloor heating system, the wire leading the current in one direction and the returning wire leading the current in the opposite direction are placed relatively far apart from one another. In this configuration, a high-intensity magnetic field (of up to 200 mG and higher in close proximity to the wires, depending on the depth of the installation of the heating system and on the level at which the measurements were carried out) is created which cannot be cancelled out by the magnetic field of the returning wire.

 

Following an intervention by the Ministry of Environmental Protection, nowadays dual wire underfloor heating systems are manufactured and sold in Israel. In this type of system the wire leading the current in one direction and the returning wire are adjacent so that the magnetic field created by one wire is cancelled out by the magnetic field of the returning wire. With this type of system, the magnetic field formed above the floor is very low (assuming that it is optimally installed).

 

In addition to having electric currents and magnetic fields, underfloor heating systems are also characterized by long operating times, thereby leading to long-term exposure to magnetic fields compared to exposure to other domestic electric appliances.

 

If you are intending to install an underfloor heating system, to minimize the exposure to magnetic fields, plan well in advance and ensure that a dual core element system has been placed optimally prior to laying the floors.

 

If you have an old underfloor heating system, it is possible to minimize the time of exposure by turning the system on before people enter the room, turning it off when the temperature is pleasant, and restarting the system when people have left the room (using a remote control or a timer).

 

Notably, there are water- and oil-based underfloor heating systems that operate by passing electrically-heated water or oil through pipes laid under the floor. Heating of the water or oil can take place in one central location within the building where energy is supplied for heating the liquid to the appropriate temperature. As high-intensity electric and magnetic fields may form in the location of the system's electric component for heating the liquid (water or oil), it is recommended to identify this location and to avoid spending a long time in its vicinity. If domestic heating is distributed through permanent smaller heating devices in the home, it is recommended to avoid spending long periods of time near such devices and to keep a distance of at least several tens of centimeters from their electric component.   

29.6.16