Philadelphia, the city of brotherly love has it. Many in San Francisco want it…
Wireless broadband Internet access (wireless) It seems too good to be true. In
relatively low cost, anyone can connect to the Internet anywhere in a city. the whole city
need to do is install WiFi antennas.
One argument in favor of city-wide Wi-Fi is that it will reduce the digital divide:
the poorer you are, the more limited your access to the Internet and its information
resources. Cities like Philadelphia and San Francisco are actively trying to shut down the
digital divide. One option is Wi-Fi.
However, when weighing the options, you hear almost nothing about the potential for health.
Risks Saturating an entire city with WiFi adds to the existing load of non-ionizing
radiation. That load, called electrosmog for some, it consists of long-term
exposure to low-level concentrations of non-ionizing radiation from familiar sources
such as radio and television signals, electronic and electrical devices, and the ubiquitous cell phone
phone.
Wireless Internet access
Local area networks (LAN) link computers, printers, modems, and other
devices. Traditional LANs physically make the links using wire cable. Publications
between computers and other devices on the network are managed by a device
called to router.
A wireless LAN eliminates the wire cable by using a router that transmits and
receives radio signals. To use a wired LAN, you must plug in your computer or other
device into a wall socket. A cable runs from the plug to the router, which manages
signal traffic between devices on the network.
With a wireless LAN, each device on the network is designed so that it can send a signal
to the router and receive the signals back. Wireless routers typically have a range of
hundreds to several hundred feet. Range can be increased by adding a booster
which increases the intensity of the signal.
As with all radio signals, the closer you are to the transmitter (the router), the more
the stronger the signal. Cell phones work on the same principle. the difference is that
cell phones operate at a different frequency and emit a stronger signal than cordless phones
LAN.
radio frequencies
Cell phones operate at frequencies in the 3 to 30 GHz range, similar to microwaves
ovens. Wireless LANs operate at one-tenth of that range: 0.3 to 3 GHz, the range of
UHF television broadcasts. GHz stands for gigaHertz, a standard measurement
of radiofrequency radiation (R.F.R.R.)–electromagnetic radiation created by
sending an alternating electrical current through an antenna. The higher the GHz,
the faster the current alternates.
Frequency alone does not measure the potential effect of RFR. how would you do it
I guess signal strength matters too. The strength of a signal is measured
in watts, a standard measure of electrical power. For example, at 100 watts
The bulb is brighter because it puts out more power than a 60-watt bulb.
Think about the effect of waves on the beach: small waves widely separated (low force, low
frequency) versus large wave very close (high force, high frequency). Tea
The former is likely to have less of an effect than the latter.
RFR exposure is measured using the SAR specific absorption rate. SAR is
expressed in milliwatts/kilogram (mW/kg) of body weight or in milliwatts/cubic
centimeter (mW/cm2) of exposed body area: the size of the wave and the amount of
your body hits
health risks
WiFi enthusiasts dismiss concerns about health risks because power output and SAR
exposure is significantly below the minimum standard set for cell phones. but cell phone
telephone standards are established for short-term exposure of a cell phone in use under pressure
to your head. In addition, the standards are set based on the thermal effect (heating)
of radiation.
Non-thermal effects of cell phones are documented at exposures below current.
American standards, including
– memory loss,
– sleep interruption,
– slow motor skills and reaction time,
– decreased immune function,
– spatial disorientation and dizziness,
– Headaches,
– reduced sperm count,
– increased blood pressure and pulse,
– DNA breakage and reduced DNA repair capacity, and
– cell proliferation.
A second problem is that cell phone exposure is intermittent, while WiFi
exposure is constant. A more accurate comparison is with the cell phone effect.
transmission antennas. These antennas send and receive radio frequency signals.
constantly.
The signal strength of an antenna is comparable to that of a cell phone only at a very short distance.
tidy. The exposure is not the brief explosion of a cell phone, but a persistent bath of low
RFR force. In addition to the documented health effects of cell phone use,
exposure to cell phone antennas includes
– increased blood pressure and pulse,
– sleep interruption,
– emotional effects such as increased depression and irritability,
– memory loss and brain fog,
– fatigue and dizziness, and
– increased risk of cancer.
Due to these effects, the International Association of Firefighters (AFL-CIO)
decided in 2004 that they will not allow cell phone masts in fire stations.
RFR hypersensitivity
Much of the discussion about the health effects of RFR is framed as a concern with people
they are hypersensitive. hypersensitivity is the technical term for allergies
and similar overreactions of the immune system. But instead of pollen, RFR
Hypersensitivity is a reaction to non-ionizing agents.
radiation. It seems like an unfortunate few are affected while the rest of us are out in the cold.
hook.
Research by Olle Johansson and Örjan Halberg of the Karolinska Institutet, Stockholm
suggests otherwise. They looked at the incidence of cancer in Europe and the US.
and found a surprising association between increases in certain types of cancer during the
20th century and RFR exposure measured by radio and television transmissions.
What the hypersensitive really represent is one extreme in a complex landscape of
effects and risks. Like any other environmental stressor, RFR will affect some
people more than others. And as with other environmental stressors, the greater the
general cargo, the greater the risk of becoming one of the “unfortunate few”.
Wireless LANs add to the existing RFR burden. As well as burning more fossil fuels
adds more smog, adding more RFR adds more electrosmog. you do not have to do it
expose your home or city to the increased load created by WiFi. There is a
viable alternative: a wired LAN. Exaggeration can make it seem less convenient and
more expensive. But what is a good night’s sleep worth? Or reduce your risk of
cancer?
Resources
International Association of Firefighters. 2004. Position on the health effects of
Radio Frequency/Microwave Radiation (RF/MW) at Fire Department Facilities
Base Stations for Antennas and Towers for the Conduction of Cellular Telephony
Transmissions. Access at http://www.iaff.org/safe/content/celltower/
torrecelularfinal.htm.
Johansson, Olle, and Doug Loranger. 2005. Electrosmog. your own health and
Physical aptitude. Streamed November 29, 2005. http://yourownhealthandfitness.org/
radiation.html.
I knew, Cindy. 2005. Comment on San Francisco TechConnect Community Wireless
Broadband Initiative. Sage Associates: September 2005.