Exposure difference to mobile phones
Mobile phone radiation and health
While users of wireless devices are typically exposed for much longer periods than for mobile phones, the range of wireless devices (and hence their strength) is significantly less. As well, the devices are located significantly farther away from users' heads, resulting in far less exposure overall: The Health Protection Agency claims that if a person spends one year in a Wi-Fi hotspot, they will receive the same dose of radio waves as if they had made a 20-minute call on a mobile phone.
Wireless LAN
EMF levels for WiFi devices are much lower than mobile phones, and there is less public concern about any suggested health issues for wireless LAN devices. Most wireless LAN equipment is designed to work within predefined standards. Wireless access points are also often in close proximity to humans, but the drop off in the already low power over distance is fast, following the inverse-square law. WiFi has been anecdotally linked to electromagnetic hypersensitivity, but no studies have researched this association to date.
The HPA's position is that “...radio frequency (RF) exposures from WiFi are likely to be lower than those from mobile phones.” It also saw “...no reason why schools and others should not use WiFi equipment.”In October 2007, the HPA launched a new “systematic” study into the effects of WiFi networks on behalf of the UK government, in order to calm fears that had appeared in the media in a recent period up to that time". Dr Michael Clark, of the HPA, says published research on mobile phones and masts does not add up to an indictment of WiFi.
Bluetooth
Bluetooth also uses the microwave frequency spectrum in the range of 2.4 GHz to 2.4835 GHz. The radiated output power of Bluetooth devices varies between 1 and 100 mW, and can operate continuously or sporadically (on demand), so total exposure to EMF radiation is quite variable. Bluetooth devices have not been linked with any health issues.
Other devices
Radio frequency in the microwave and radio spectrum is used in a number of practical devices for professional and home use, such as:
- DECT and other cordless phones operating at a wide range of frequencies
- Remote control devices for opening gates, etc.
- Portable two-way radio communication devices, such as walkie-talkies
- Wireless security (alarm) systems
- Wireless security video cameras
- Radio links between buildings for data communication
- Baby monitors
In addition, electrical and electronic devices of all kinds emit EM fields around their working circuits, generated by oscillating currents. Humans are in daily contact with computers, video display monitors, TV screens, microwave ovens, fluorescent lamps, electric motors of several kinds (such as washing machines, kitchen appliances [like electric can openers, blenders, and mixers], water pumps, etc.) and many others. The typical background power of electromagnetic fields in the home can vary from zero to 5 milliwatts per meter squared. Long-time effects of these electromagnetic fields on human and animal health are still unknown, and most of the studies available have shown no effect. However, the powerful fields produced by radio (and then TV) transmitters have been present for more than 100 years now with no established effects on people's health.
Health Research Programs
Extensive research has been conducted into possible health effects of exposure to many types of radio signals.
The consensus of scientific reviews to date is that there are no established adverse health effects from exposures to radio signals at levels below the 1998 guidelines of the International Commission on Non-Ionizing Radiation Protection (ICNIRP). When weighing the evidence for potential health effects, scientists consider different aspects before drawing their conclusions:
Health Research Programs
Extensive research has been conducted into possible health effects of exposure to many types of radio signals.
The consensus of scientific reviews to date is that there are no established adverse health effects from exposures to radio signals at levels below the 1998 guidelines of the International Commission on Non-Ionizing Radiation Protection (ICNIRP). When weighing the evidence for potential health effects, scientists consider different aspects before drawing their conclusions:
- Have the effects been reported in the scientific peer reviewed literature?
- Have the reported effects been independently replicated?
- Is there a credible mechanism of action for the reported effects?
- Do the reported effects have any health significance?
- What is the strength of the reported effect?
- Do the reported effects exhibit a dose-response relationship?
- Is the study 'hypothesis testing' or 'hypothesis generating'?
- Have the statistical analyses of the results been conducted properly?
- Are there more obvious explanations for the reported outcomes?
- How does this study fit into the total existing research body?
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