Wi-Fi and your health: Is there really a risk? Wi-Fi is a device used to connect electronic devices wirelessly. A Wi-Fi enabled device—a personal computer, video game console, smart phone or digital audio player—can connect to the Internet via a wireless network access point.
An access point, or hotspot, has a range of about 20 meters (65 feet) indoors and a greater range outdoors. Multiple overlapping access points are used to cover areas as large as many square kilometers.
Wi-Fi users can access and share data, applications, Internet access or other network resources in the same way these are shared in wired systems.
To allow wireless connections, Wi-Fi devices must be equipped with antennas that transmit and receive radio waves. Devices operate in certain frequency bands near 2.4 and five gigahertz (GHz).
Wireless technology relies on an extensive network of fixed antennas, or base stations, relaying information with radiofrequency (RF) signals. There are over 1.4 million base stations in the world today, and the number is increasing with the introduction of third generation technology.
Next to cell phones, Wi-Fi is today the second most common form of wireless technology. Widely used in schools, offices, coffee shops, homes as well as countless other locations across the world, its use is spreading.
Today, over 700 million people use Wi-Fi . There are over four million hotspots around the world and about 800 million new Wi-Fi devices are sold every year.
Other wireless networks that allow high-speed Internet access and services, like wireless local area networks (WLANs), are also becoming more common.
But as the numbers of Wi-Fi devices, base stations and local wireless networks increase, so does the exposure of people to RF signals.
People using Wi-Fi, or those close to Wi-Fi equipment, are exposed to the radio signals it emits and some of the transmitted energy in the signals is absorbed in their bodies.
International health agencies—the World Health Organization, the United States Center for Disease and Control, Health Canada, the European Environmental Agency and the United Kingdom’s Health Protection Agency—say the radiofrequency energy emitted from Wi-Fi equipment is extremely low and does not cause any health problems.
Despite growing concern over the health effects of Wi-Fi use and low-level but long-term exposure to RF energy, these health agencies say that currently, there is still no consistent evidence to show that exposure to radio signals from Wi-Fi and WLANs is dangerous.
The signals are very low power, typically 0.1 watt (100 milliwatts), in both computers and routers (access point). This is well below safety limits developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP, 1998) and the Institute of Electrical and Electronic Engineers (IEEE, 2005).
The RF exposure from base stations are only 0.002 percent to two percent of international safety levels, WHO says.
This is also lower or comparable to RF exposure from radio or television broadcast transmitters, and lower than those from mobile phones.
People, in fact, routinely absorb up to five times more signals from FM radio and TV than from base stations, WHO says.
This is because of their lower frequency—frequencies used in FM radio are around 100 MHz and in TV broadcasting these are around 300 to 400 MHz, while those used in mobile telephony are 900 MHz and 1800 MHz—and because a person’s height makes the body an efficient receiving antenna.
Radio and TV broadcast stations have been operating over the past 50 or more years and no adverse health consequence have since been reported, WHO notes.
According to WHO, as long as exposure is below established limits, Wi-Fi is not dangerous to people.