Proceedings of National Conference on New Horizons in IT - NCNHIT 2013
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Electro - Magnetic Radiation
A Friend or a Foe? Prevention Better than Cure!
Dr. Vinod Moreshwar Vaze
Abstract---- Over the period of the technology has grown
many folds. Communication Towers are being built at a
phenomenal rate. May be there is one right in front of your
balcony! Is it good for you? This paper will make you think
again. In additions to the goodies it carries, it also carries
electro-magnetic radiations which may be harmful to you and
your family. How does the common man shield himself from
the hazardous electro-magnetic radiations which are
unsolicited members entering his bedroom, living room and
balcony where he is staying along with his, grandparents,
senior citizens and that too 24x7. An unknown enemy is
constantly hammering on their body and giving rise to
unwanted health problems. Sometimes the effects can be
simple things like weakness, nausea, but sometimes they can
be as serious as leukemia and other cancer. This paper first
discusses the technical aspects of the issue and then makes the
reader aware of the caveats of electromagnetic radiation and
at the end suggests a few remedies for a common man who
may or may not be computer savvy. Theme: prevention is
better than cure.
Keywords--- Electromagnetic Radiation, Health Effects,
Remedial Solutions, Shield Yourself
market. The faster a company picks up the ways and means to
implement a new technology the better would be its shares in
the corporate market. Some companies needs to fight for their
sustainability as a leader whereas many need to fight to
survive in the market. This is also good and healthy for the
country. We support it. We encourage it because that is the
way the society becomes stronger wealthier.
1.2 The caveats: However, not many companies look into
the other side of the same coin. Yes the Health! This paper
deals with the health hazards of electromagnetic radiation. It is
the colourless, odourless, and invisible, you cannot neither feel
nor touch it. And these are the main obstacles of spreading of
the awareness in the society as on today.
1.3 The challenges: The attempt of this paper is to make
the reader see the “RED” colour of danger, smell the stinky
odour of nausea, visible signs of cancer, and the feel of
downward falling vigor & touch of the unhealthy and sick
scenario in your family and friends.
Thus the need is created to first study and then to make
others aware of the caveats of electromagnetic radiation on
human health.
II.
I.
INTRODUCTION
"Mr. Watson, come here, I want you!" – A historical
sentence which puts you in the past. That is the first sentence
that was ever communicated on a telephone. On March 10,
1876, in Boston, Massachusetts, Alexander Graham Bell
invented the telephone. Since then we have come a long long
way. From 1G to 2G to 3G to 4G and now even 5G, the
growth is exponential.
1.1 The trend: The general trends of the society is that they
want a smaller handheld device, faster data transfer, larger
range of coverage, cheaper in cost, multimedia facilities, and
user friendly technology. These facts lead to innovative use of
present technologies and a research for better technologies.
This is good and healthy for the country. All these demands of
the society are reasonable and the cut throat competition in the
market makes the manufacturing companies keep doing
research. Good signs. That is exactly the way a society grows.
This breeds better and better technologies appear in the
Dr. Vinod Moreshwar Vaze, MCA Coordinator, IDOL Institute of
Distance and Open Learning, University of Mumbai. E-mail:
[email protected]
B.Tech. I.I.T.Kanpur, PGDFM (Bom) Post Graduate Diploma in Cyber
Law, Ph.D. (Internet Security)
TECHNICAL BACKGROUND
2.1 The range: Electromagnetic radiation covers a wide
range of frequency spectrum from ELF (extremely low
frequency f=100 Hzs; λ= 106 meters) to gamma ( γ) rays (f=
1019 Hzs; 10exaherzs, λ= 10-12 meters = 10 picometers) 1
picometer = micro-micro = μµ = 1 e−12 meters
2.1.1
2.1.2
2.1.3
2.1.4
2.1.5
2.1.6
2.1.7
ISBN 978-93-82338-79-6
Lower frequencies allow carriers to provide
coverage over a larger area, while higher
frequencies allow carriers to provide service to
more customers in a smaller area.
Any frequency below 3,00,000 (Three lacks) Hz
is not practical for use by any electrical devices.
Lower the frequency broader is the radiation of
transmitted signal. Higher the frequency more
tightly focused in the transmitted beam.
Lower the frequency more persistent is the signal.
Higher the frequencies make it more fragile.
Lower the frequency lower the bandwidth, Higher
the frequency higher the bandwidth.
Lower the frequency, higher the wavelength,
Higher the frequency lower the wave length.
Lower the frequency lower the Photon energy,
Higher the frequency higher the photon energy,
so (gamma ray photons have the highest energy)
Proceedings of National Conference on New Horizons in IT - NCNHIT 2013
2.1.8
Last but the most important: Higher the frequency
higher the vulnerability of health hazard.
III.
CLASSIFICATION
The electromagnetic radiation can be classified in two
categories:
3.1 Ionizing (frequency more than Ultra Violet)
3.2 And Non ionizing (frequency less than Ultra Violet)
This paper will not discuss the entire range of
electromagnetic spectrum. We shall restrict ourselves to nonionizing and further restrict to most disputed range: 300 MHz
1 GHzs = (10)9 Hzs to 100 GHzs = (10)11Hzs.
3.3 900 MHz v/s 2.4 GHz (IEEE 802.11b)
3.3.1 Free space loss: The attenuation over distance favors
900 MHz over 2.4 GHz. At any given distance the free space
loss at 2.4 GHz is 8.5 dB larger than at 900 MHz.
3.3.2 Antenna gains: In order to cover long distances you
will need high gain antennas. The gain of a reflector type
antenna goes up as you increase the area of the parabolic
surface. But for a given physical size, the antenna gain at 2.4
GHz is significantly higher than an antenna at 900 MHz.
Frequency
300 Mhz
900 MHz
1.0 GHz
2.4 GHz
5.6 GHz
8.0 GHz
9.6 GHz
30 GHz
100 GHz
Wavelength
100.0 cms
33.31 cms
29.98 cms
12.491 cms
5.3534 cms
3.7474 cms
3.1228 cms
1.0000 cm
0. 29979 cms
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3.3.3. Long Links: On very long distance links several
factors contribute to the radio link performance. Even though
the free space loss at 900 MHz is lower than at 2.4 GHz, when
you consider the typical antenna gains and antenna heights
required to clear obstructions, a 2.4 GHz radio often has the
advantage. For a fixed point-to-point link, the FCC rules
favour the 2.4 GHz allowing considerable larger transmit
power which translates to increased distance.
3.4 GHz (IEEE 802.11b) v/s 5.6 GHz (IEEE 802.11a)
3.4.1 Common trend: 2.4 GHz devices are commonplace
today. But with the development of 802.11a, 5.6GHz devices
are beginning to surface. [1] Whether you are testing or
installing 802.11b, 802.11a, or 802.11g, [1] the vulnerabilities
are the same. [1] Range considered: 1GHz (-100db) to 6 GHz
(-80db)
3.4.2 Range matters: As discussed before the higher the
frequency of a wireless signal, the shorter is its range. Thus,
2.4 GHz networks cover a substantially larger range than 5
GHz wireless networks. [6] In particular, the higher frequency
wireless signals of 5 GHz networks do not penetrate solid
objects nearly as well as do 2.4 GHz signals, limiting their
reach inside homes. [6] The table below clearly indicates that
the photon energy for 2.4 GHz devices is about 10 e-6 eV
suddenly rises to 23 e-6 eV which is more than double harmful.
Photon energy
1.2407e-6 eV
3.7221e-6 eV
4.1357e-6 eV
9.9256 e-6 eV
23.160 e-6 eV
33.085 e-6 eV
39.702 e-6 eV
124.070e-6 eV
413.57 e-6 eV
3.4.3 What is Photon Energy?
A photon is a discrete bundle (or quantum) of
electromagnetic (or light) energy. If the individual molecules
within the material vibrate at a greater frequency we say that
the material has greater internal energy. Thus we can say that
when electrons within an atom have greater energy, they orbit
faster. To generate a higher frequency light wave, we need
higher energy. The reaction that produces the wave is a
reaction that gives up greater energy per photon.
3.4.4 What is a photon?
A photon is an elementary, mass-less particle of light. A
beam of light is a great many photons moving together. When
an electron drops from an excited state to its ground state, the
electron releases one photon. For an electron, energy can show
up as a combination of speed and mass. For a photon, mass is
zero and speed is always the same. Therefore as on today the
frequency is the only variable available to act as the indicator
of the photon’s energy.
Watt-second or Joules
1.9878214 e-25
5.9635
e-25
6.6261247 e-25
1.5902571 e-24
3.7106426 e-24
5.3008036 e-24
6.3609644 e-24
1.9878214 e-23
6.6261247 e-23
3.4.5 Properties of a Photon:
•
•
Photons move at a constant velocity, c (velocity of light)
Photons have zero mass and zero rest energy.
•
Photon carries energy (E) and momentum (ρ), which are
also related to the frequency (ν) (nu) and wavelength λ
(lambda) of the electromagnetic wave by E = h ν and ρ =
h / λ. (where h = planck's constant 6.3 x 10-34)
Photons can be destroyed /created when radiation is
absorbed /emitted.
•
ISBN 978-93-82338-79-6
Proceedings of National Conference on New Horizons in IT - NCNHIT 2013
45
1.
3.4.6 Wireless v/s mobile users
Users of wireless devices are typically exposed for much
longer periods than for mobile phones and the strength of
wireless devices is not significantly less. Whereas a mobile
phone can range from 21dBm (125 mW) for Power Class 4 to
33 dBm (2W) for Power class 1, a wireless router can range
from a typical 15 dBm (30 mW) strength to 27 dBm
(500 mW) on the high end.
However, wireless routers are typically located
significantly farther away from users' heads than a mobile
phone the user is handling, resulting in far less exposure
overall. The Health Protection Agency (HPA) 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.
IV.
BASIC CONCEPTS OF RADIATION PROTECTION
4.1 Time: The amount of radiation exposure increases
and decreases with the time people spend near the
source of radiation.
4.2 Distance: The farther away people are from a
radiation source, the less their exposure.
4.3 Shielding: The greater the shielding around a
radiation source, the smaller the exposure.
• Radiation having a wide range of energies form the
electromagnetic spectrum is illustrated below.
• The spectrum has two major divisions:
1. non-ionizing radiation
2. ionizing radiation
• Radiation that has enough energy to move atoms in a
molecule around or cause them to vibrate, but not
enough to remove electrons, is referred to as "nonionizing radiation." Examples of this kind of
radiation are sound waves, visible light, and
microwaves.
• Radiation that falls within the ionizing radiation
range has enough energy to remove tightly bound
electrons from atoms, thus creating ions.
V.
PRECAUTIONARY MEASURES
Some precautions that you can take to reduce your
exposure to the radiation from mobile phones are:
Limit your use, talk for short durations and switch
sides during long conversations.
2. Use SMS/IM chat whenever possible.
3. Use the land-line, whenever possible
4. Use speakerphone or wired hands-free, but keep the
phone at least 1 feet away.
5. When not in use, keep the mobile phone away from
your body as they still continue to emit some radiation
while trying to communicate with the base station by
sending at least one pulse per minute.
6. Do not keep it in your pocket, under your pillow etc.
7. Use cell phones with lower Specific Absorption Rate
(SAR) values. One can find the SAR value of a phone
by simply searching- <Company Name> <Model
No.> SAR. The lower the SAR value, the less
dangerous it is. Ideally go for a phone which has SAR
value – 0.2 – 0.8 W/Kg [3]
Electromagnetic radiation is a
colourless, odourless, tasteless &
noiseless enemy. How can one detect if
your home/ place of work in under
attack?
5.2 What is ICNIRP?
International Commission on NonIonizing Radiation Protection.
India had adopted radiation norms
specified by ICNIRP Guidelines for cell
tower radiation, which states that safe
Power density = f / 200, where f is in
MHz.
For f = 900 MHz, Safe Power density
= 4.5 W/ m2 = 4,500,000 μW/ m2
For f = 1800 MHz, Safe Power density = 9.0 W/ m2 =
9,000,000 μW/ m2
For detection, NESA has come up with a low cost, simple
and easy to use Cell Tower Radiation Detector, DETEX 189.
The radiation levels are indicated by three LEDs (Light
Emitting Diodes) - Green, Yellow and Red.
A common man can use this indicator as well as buzzer to
find if one is living in a safe, caution or danger zone.
A day-to-day example: Every microwave oven has a
window to look into. The oven uses microwaves with
wavelengths (λ) of 12 cm. The body of the oven is a Faraday
cage formed by the oven's metal housing. Visible light, with
wavelengths ranging between 400 nm and 700 nm, passes
easily through the screen holes.
Any holes in the shield or mesh must be significantly
smaller than the wavelength (λ) of the radiation that is being
kept out, or otherwise the enclosure will not be as effectively
as a sheet of conducting surface. A simple large-mesh screen
shield can work well for lower frequencies, but can be
ineffective for microwaves.
ISBN 978-93-82338-79-6
Proceedings of National Conference on New Horizons in IT - NCNHIT 2013
ACKNOWLEDGMENT
I wish to express my gratitude to the following:
1.
Mr. M. R. Khambete, Founder President Thane Small
Scale Industries association. Thane
2.
Dr. Mahu Gupta, my Ph.D. guide
3.
Dr. P. Joglekar, ex-professor. I.I.T. Delhi
REFERENCES
Bibliography: (In APA format)
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
Ramsey Electronics (2006-2013)
http://ramseytest.com/?gclid=CK_SkMHx3rkCFcYF4godjxkAOQ
http://www.thomasnet.com/articles/custom-manufacturingfabricating/radiation-shielding-materials
http://en.wikipedia.org/wiki/Radiation_protection
http://www.epa.gov/radiation/understand/protection_basics.html
http://www.nealloys.com/hymu_80.php?gclid=COvhmrHw3rkCFSQ44g
odbh8A8w
Bradley Mitchell, (2013) About.com Guide Is 5 GHz Wi-Fi Network
Hardware Better
http://compnetworking.about.com/od/wirelessfaqs/f/5ghz-gear.htm
http://www.epa.gov/radiation/understand/ionize_nonionize.html
http://www.ncbi.nlm.nih.gov/pubmed/95879 Prof. Girish Kumar (2010),
Report on Cell Tower Radiation. Department of Electrical Engineering,
Indian Institute of Technology Bombay.
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