| What is WiFi? It is possible to form a somewhat | | | | recommended levels and there is no evidence of |
| informed opinion on the safety or potential risks | | | | any risk to humans. Yet some people blame WiFi |
| of this new technology without actually being a | | | | exposure for everything from sleep disturbances, |
| physicist yourself. Quite simply, Wi-Fi is the | | | | headaches and blurred vision, to heart and |
| wireless technology most commonly used to | | | | breathing problems. |
| connect people to the Internet in schools, coffee | | | | Because no study has ever shown a conclusive |
| shops, hotels and other network locations, or to | | | | risk to human health from exposure to these |
| connect cell phone users to one another. Wi-Fi is | | | | low-frequency radio transmissions, many simply |
| certainly convenient for travelers and students, | | | | shrug off the complaints of these people, |
| but is it dangerous? Many believe that the | | | | choosing to believe their symptoms are |
| low-level electromagnetic waves that radiate from | | | | coincidental or caused by another source. |
| the wireless Internet source to each individual | | | | So just how high are the levels of radiation in a |
| user can be harmful to your health, even causing | | | | hotspot? According to Dr. Michael Clark of the |
| cellular changes and possibly cancer in some cases. | | | | HPA, the published research on mobile phones and |
| The area covered by a WiFi Internet connection | | | | wireless networks does not indicate a risk to |
| is known as a "hotspot"; this is the area in which | | | | human health. "All the expert reviews done here |
| the waves radiate to give users access to the | | | | and abroad indicate that there is unlikely to be a |
| world wide web. It can span several kilometers, | | | | health risk from wireless networks" he says. "The |
| although the waves cannot pass through treed | | | | few studies on cellular phone masts that have |
| areas. While in the hotspot, a laptop user can | | | | appeared in peer-reviewed journals claiming to |
| simply connect to the network, access the | | | | observe health effects are not at all conclusive. |
| Internet, and check their Email or do their other | | | | The real problem is deciding what level of |
| business on the run. | | | | precaution is appropriate. |
| A wireless network uses radio waves to send | | | | "When we have conducted measurements in |
| communications across a two-way network. A | | | | schools, typical exposures from wifi are around |
| computer's wireless adapter translates the | | | | 20 millionths of the international guideline levels of |
| Internet connection data into a radio wave and | | | | exposure to radiation. As a comparison, a child on |
| sends it to the wireless router - the one in your | | | | a mobile phone receives up to 50% of guideline |
| laptop. This process works in reverse as well, | | | | levels. So a year sitting in a classroom near a |
| sending a radio signal back to the host computer. | | | | wireless network is roughly equivalent to 20 |
| Hotspots Useful Stations or Environmental | | | | minutes on a mobile. If wi-fi should be taken out |
| Hazards? | | | | of schools, then the mobile phone network should |
| Some report an unusual sensitivity to the waves | | | | be shut down, too - and FM Radio and TV, as the |
| emitted in these hotspots. Officially, the levels of | | | | strength of their signals is similar to that from |
| WiFi electromagnetic radiation emitted into the | | | | wi-fi in classrooms. |
| environment in a hotspot are well below | | | | |