FAQ
Radiation-Emitting Household Appliances
Is there exposure to radiation from a computer scanner?
Scanners for home use are marketed in two ways – standalone scanners (also called “table scanners”) and all-in-one printer scanners (multifunction printers that include scanners).
- Standalone scanners contain 3 elements which may have the potential for radiation exposure:
- Power supply cables (direct connection to the electricity grid and sometimes power supply from the computer). There is some exposure to magnetic and electric fields in the electricity grid frequency (a frequency which belongs to the low frequency/ extremely low frequency - ELF) in the vicinity of the electrical cables. Since the electric current strength in the power cables is low, the exposure levels in their vicinity are even lower. Also, there is a cable connecting the scanner to the computer for data transfer (usually a USB cable). The voltages and the currents in this cable are very low, and the exposure levels in its vicinity are negligible.
- Wireless connection to the local Wi-Fi network constitutes a source of radiofrequency radiation in the region of the wireless network including the scanner. The typical radiation strength of the Wi-Fi network sources is relatively small, and in this case, in accordance with the precautionary principle, keeping tens of centimeters from the scanner is a reasonable safe distance.
- The optic laser (which is part of the scanner components) also constitutes a source of radiation emission. The US Occupational Safety and Health Administration defines the dangers of exposure to the optic laser of a scanner at a level similar to that of exposure to light coming from devices such as an optic computer mouse. Care should be taken not to look straight at the scanner light while it is operating.
- Multifunction printers with scanner capability – in addition to the 3 elements mentioned above that constitute a potential source of radiation exposure, in a combined scanner, there is also the potential for exposure to chemicals evaporating from the scanner-laser printer toner during any printing activity. Therefore, care should be taken to ventilate the area of the equipment well and to refrain from spending prolonged times close to the printer during heavy and prolonged printing.
Is There Radiation from Induction Cooktops?
Induction cooktops (stoves) are based on the creation of Very Low Frequency (VLF) magnetic fields up to tens of kHz (usually in the range of 20-30 kHz). Those magnetic fields are immersed in metallic heater mounted on the stove, which induces electrical currents inside them. The electric currents cause heating of the bottom of heating utensils (pot, pan, etc.), and, consequently, heating of the food in the utensils. When the stove stops working, the electrical current inside it is interrupted and so are the magnetic fields around it. The fields are completely reset and not stored in the heated food.
The magnetic fields generated near the stove, to which the person cooking is exposed, are usually at the levels of several microTesla (millionths of Tesla), and are usually below the maximum exposure levels of the ICNIRP (International Commission on Non-Ionizing Radiation) guidelines (although in adjoining the cooker physically, those levels can be exceeded in certain situations). It should be noted that the fields fade sharply as the distance from the stove increases.
For the purpose of preserving the precautionary principle of reducing exposure, it is recommended to maintain a separation distance from the stove and operate it according to the manufacturer's instructions; among other things, operate them with cookware on them, use appropriate induction heating utensils, and place them in the center of the hobs.
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 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
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 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:
- Extremely low frequency (ELF) emitted from the computer as an electric device.
- 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?"
