Radiation-Emitting Household Appliances
Radiation-Emitting Household Appliances
Do underfloor heating systems cause exposure to non-ionizing radiation?
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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 |
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
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 for use of nail dryers?
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Most nail dryers are based on bulbs emitting ultraviolet radiation (UV-A). Some drying devices are based on LED bulbs. |
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.
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.
