mini project documentation
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ELECTRO POLLUTION IT’S HAZARDSAND PREVENTION
CHAPTER-1
INTRODUCTION
1.1 Pollution:
Pollution is the introduction of contaminants into a natural environment that causes
instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or
living organisms.pollution making our life miserable on earth. The culprits of
damaging the nature’s gift are humanbeings, in which some are directly involved and
others indirectly. The directly involved sources are industries,defence,medical etc.The
indirectly involved sources are users in the form of entertainment,domestic and
simplicity etc. with Pollution in life, Earth is becoming disturbed; sooner or later
causing dramatic changes in its surface. Nevertheless, Pollution is simultaneously
endangering life in Earth. Pollution is becoming closer to put life on the threshold of
death. These harmful actions have changed Earth, and they continue to do so today.
Types of pollutions are airpollution,landpollution,waterpollution,thermalpollution
noise Pollution,radioactive pollution,electro polution,soil pollution,chemical pollution
& lightPollution etc. Among these,electropollution has been greatest health risk of 21st
centuary.
The reason for this concern is unprecedented increase that has occurred in recent
years in the number and variety of EMF sources,that which emit electromagnetic
radiation whether from personal appliances use or from commercial and industrial
applications. these unprecedented in technologies (especially wireless
communications) and with in turn an exponential increase in electropollution .These
unprecedented increase in technologies (especially wireless telecommunications) and
with in turn an exponential increase in ElectroPollution.
1.2 Electromagnetic Radiation
Energy is in the form of transverse magnetic and electric waves. In a vacuum,wave
travel at the speed of light (which is itself a form of electromagnetic radiation). The
acceleration at the speed of light(which itself a form of electromagnetic
radaiation).The acceleration at the speed of light (which is itself a form of
electromagnetic radiation). The acceleration of electric charges (such as alternating
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current in a radio transmitter) gives rise to electromagnetic radaiation.A single unit, or
quantum, of electromagnetic radiation is called a photon. In the nineteenth century,
physicists discovered that a changing electric field creates a magnetic field and vice
versa. Thus a variation in an electric field (for example, the changing field created
when a charged particle such as an electron moves up and down) will generate a
magnetic field, which in turn induces an electric field.
Equations formulated by James Clerk Maxwell predicted that these fields could
potentially reinforce each other, creating an electromagnetic ripple that propagates
through space. In fact, visible light and all other forms of electromagnetic radiation
consist exactly of such waves of mutually reinforcing electric and magnetic fields,
traveling at the speed of light. The frequency of the radiation determines how it
interacts with charged particles, especially with the electrons of atoms, which absorb
and reemit the radiation.The energy of the electromagnetic radiation is proportional to
its frequency.The greater the frequency of the waves, the greater their energy.
FIG 1.1 ELECTROMAGNETIC WAVE
Electropollution radiation can also be conceived of as streams of particles known as
Photons. The photon is the quantum of electromagnetic radiation.In qunantam
mechanics , all phenomena in which charged particles interact with one another, as in
the binding of protons and electrons in an atom or the formation of chemical bonds
between atoms in a molecule, can be understood as an exchange of photons by
charged particles.
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1.2 Electro Magnetic Spectrum
Electromagnetic radiation is classified according to the frequency of its wave.
Electromagnetic spectrum, in order of increasing frequency and decreasing
wavelength, consists of radio waves, microwaves, infrared radiation, visible light,
ultraviolet radiation, X-rays and gamma rays.
Radiowaves(3kHz -300GHz)
Microwaves(300 mHz-300GHz)
Infrared waves(1-400THz)
Visible light(490-700THz)
Ultraviolet radiation(7.5*10^14hz-3*10^16hz)
X-rays(30 petahertz-30 exa hertz)
Gamma rays(>exa hertz)
FIG 1.2 ELECTROMAGNETIC SPECTRUM
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1.3 Nature of Electromagnetic Fields
Electropollution is basically the invisible electromagnetic energies emitted from
various objects which rely on electricity to operate. Devices that utilize electricity
often emanate electropollution. Electromagnetic fields are invisible and cannot be
seen or smelled. The latter waves are detectable by a special device like smartfield
meter which detects the waves as they emanate from electrically charged objects.
These waves are considered dangerous in many instances and have been associated
with a number of health concerns and issues. Differences in voltage are what cause
variances in electromagnetic fields the higher the voltage is, the more powerful the
electromagnetic fields are which emanate from electrically charged objects. Even if
the device has no power flowing to it, an electromagnetic field can be generated from
a device. The more that one is distanced from the original source, which emanates the
EMF waves, the better: distances weaken the electromagnetic wave strength.
FIG 1.3 ELECTROMAGNETIV WAVE WITH FIELD DIRECTIONS
Energy is in the form of transverse magnetic and electric waves. In a vacuum,wave
travel the speed of light (which is itself a form of electromagnetic radiation).
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Theacceleration at the speed of light (which is itself a form of electromagnetic
radiation). The acceleration of electric charges (such as alternating current in a radio
transmitter) gives rise to electromagnetic radaiation.A single unit, or quantum, of
electromagnetic radiation is called a photon.
physicists discovered that a changing electric field creates a magnetic field and vice
versa.Thus a variation in an electric field (for example, the changing field created
when a charged particle such as an electron moves up and down) will generate a
magnetic field, which in turn induces an electric field. Equations formulated by James
Clerk Maxwell predicted that these fields could potentially reinforce each other,
creating an electro magnetic. In fact, visible light and all other forms of
electromagnetic radiation consist exactly of such waves of mutually reinforcing
electric and magnetic fields, traveling at the speed of light. Electromagnetic radiation
travels through space in the form of waves. It's hard to imagine radiation moving as
waves through empty space without a medium to transfer the wave form. The waves
created when you drop a rock into a pool require molecules of water to propagate
them, but not so for radiation.The frequency of the radiation determines how it
interacts with charged particles, especially with the electrons of atoms, which absorb
and reemit the radiation.
Electromagnetic radiation has the dual nature,As its exhibits
1)wave properties
2)particulate (photon) properties.
Wave nature of radiation:
Radiation can be thought of as a traveling transversewave..Figure 1.1 A schematic
view of an electromagnetic wave propagating along the axis. The electric and
magnetic fields oscillate in the x-y plane and perpendicular to the direction of
propagation z-axis.
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FIG 1.4 WAVE NATURE OF RADIATION
Since all types of electromagnetic radiation travel at the speed of light, short-
wavelength radiation must have a high frequency.Unlike speed of light &wavelength,
which change as electromagnetic energy is propagated through media of different
densities, frequency remains constant and is therefore a more fundamental property.
Particulate nature of radiation:
Radiation can be also described in terms of particles of energy, called photons.
The energy of a photon is given as:
= h = h c=hc
where h is Plank’s constant (h = 6.6256x10-34 J s). The above relates energy of each
photon of the radiation to the electromagneticwave characteristics ( ~and
Photon has energy but it has no mass and no charge.
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CHAPTER-2
ELECTROPOLLUTION
2.1 Defination
Nonionizing electromagnetic radiation propagated through the atmosphere by
broadcast towers, radar installations, and microwave appliances, and the magnetic
fields surrounding electrical appliances and power lines, which is believedhave
polluting effects on people and the environment;it is also also called as electrosmog
“Electropollution” is a term that describes our increasing exposure to harmful
invisible electronic frequencies harnessed by man in our modern world. Electronic
frequency can be divided into these basic groups:
Extremely Low Frequency (ELF): Power lines
Radio Frequency (RF): radio and tv signals, microwaves, and wireless devices
Intermediate frequencies: dirty electricity emitted by appliances, electric circuits, etc.
High Frequency: ionizing radiation, X-rays and CAT Scans, which have been proven
to cause cancer.
Extremely low frequency (ELF)
It is a term used to describe radiation frequencies from 3 to 300 HzIn atmosphere
science, an alternative definition is usually given, from 3 Hz to 3 kHz.In the related
magnetosphere science, the lower frequency electromagnetic oscillations (pulsations
occurring below ~3 Hz) are considered to lie in the ULF range, which is thus also
defined differently from the ITU Radio Bands. In electromagnetic therapy and
electromagnetic radiation and health research, electromagnetic spectrum frequencies
between 0 and 100 hertz are considered extremely low-frequency fields. A common
source of ELF fields in the United States is 60 Hz electric and magnetic fields from
high-voltage electric power transmission lines and secondary distribution lines, such
as those found in residential neighbourhoods.
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Radio frequency (RF)
It is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds
to the frequency of radio waves, and the alternating currents which carry radio
signals. RF usually refers to electrical rather than mechanical oscillations, although
mechanical RF systems do exist. n order to receive radio signals an antenna must be
used. However, since the antenna will pick up thousands of radio signals at a time, a
radio tuner is necessary to tune in to a particular frequency (or frequency range).This
is typically done via a resonator – in its simplest form, a circuit with a capacitor and
an inductor forming a tuned circuit. The resonator amplifies oscillations within a
particular frequency band, while reducing oscillations at other frequencies outside the
band.
Intermediate frequencies
Intermediate frequencies are, in the frame of this report, defined as frequencies
between 300 Hz and 100 kHz. They involve two different mechanisms, namely
induced currents and dielectric absorption. The frequency limit when one
predominates over the other is not precisely defined. Existence of effects depends
upon two superimposed phenomena: absorption of the external field in the organism
at the macroscopic level and the stimulation of biological effects by the penetrating
fields.
High frequency (HF)
radio frequencies are between 3 and 30 MHZ. Also known as the decameter band or
decameter wave as the wavelengths range from one to ten decameters (ten to one
hundred metres). Frequencies immediately below HF are denoted Medium-frequency
(MF), and the next higher frequencies are known as Very high frequency (VHF).
Shortwave (2.310 - 25.820 MHz) overlaps and is slightly lower than HF. ince the
ionosphere often refracts HF radio waves quite well (a phenomenon known as
skywave propagation), this range is extensively used for medium and long range radio
communication. However, suitability of this portion of the spectrum for such
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communication varies greatly with a complex combination of factors:
Sunlight/darkness at site of transmission and reception
Transmitter/receiver proximity to terminator
2.2 Electropollution Humans Role
We are immersed in a world of technology, unable to escape from the moment our
electronic alarm clocks awake us in the morning until the moment we snuggle under
our electric blankets at the end of the day. Unfortunately, today we are faced with
illnesses that were rare if not completely unheard of just a short century ago. While
our technology continues to advance us to new heights, very little attention has been
paid to the toll that such feats are exacting on our health. And it was not until very
recently that a focus has been placed on the dangers associated with the very
“conveniences” that were intended to improve the quality of our lives.
The explosion of iPhones, Blackberries, WiFi, WiMax, video game consoles and even
remote-control toys has fundamentally changed our electrical environment. You can’t
see it, you can’t taste it, you can’t touch it; but the air all around us is increasingly
filled with electromagnetic radiation (EMR) that is penetrating our bodies and
disrupting our body chemistry – perhaps forever.humansrole in creating
electropollution:
Development of radiation sources
Increasing needs and expectations
Simplicity
Development of Radiation Sources:
Ionising radiation sources : Use of radiation grew manifold after artificial
radioactive materials were produced and the first such artificial radioactive material
was Phosphorus-30 produced in 1934. Since then many such radioactive substances
have been produced and utilized for the benefit of society and their applications have
spanned many fields such as research, health care, industry, food and agriculture.
Radiation occurs in many forms, but the most important types are those which are
able to pass through matter such as X-rays and gammarays; or have high energies
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which can be used for some sort of processing,say melting of metals using high power
lasers or cross-linking cables using electron beams. Sources of radiation can be
radioisotopes,research reactors, machines such as accelerators, X-ray generators and
lasres etc.
Non-ionising radiation sources:
As these radiation sources have a wide range of applications,so that there is stent for
these development of radiation sourcesNon-Ionizing radiation originates from various
sources: Natural origin (such as sunlight or lightning discharges etc.) and man made
(seen in wireless communications, Industrial, scientific and medical applications)
FIG 2.1 IONISING AND NON IONISING RADIATION
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Increasing needs and expectations
We have been raised with the luxuries of modern appliances to simplify our lives.
Technology makes life easier, longer. we depend on technology to life our lives as
they are today. The wide application of industrial, commercial and military devices and
systems which radiate frequencies in the radiofrequency and microwave portion
of the electromagnetic spectrumOur most powerful 21st-century technologies -
robotics, genetic engineering, and nanotech - are threatening to make humans an
endangered species we do depend too much on technology. Life would never be better
without technology.. How many can grow their own garden, butcher their own meat,
enjoy an evening without TV, sitting in front of a bonfire? When the electric goes out,
what does everyone do?? Run for the flash lights and battery operated radios/TVs.
Who uses candles anymore? Except to make the place smell better? Technology can
help, but it can also cause us to forgo the past, or even our future. People need to
relearn how to grow gardens and butcher their own meat, be it deer, cow, pig, or fowl.
I know I would not have any problems surviving if technology failed us. A medical
technology, which saved millions of human lives, for instance, with the advancment
we have made in cancer research or AIDS, (these diseases have been around long
before the technology but we made no impass in their treatment until the technology
So people are depending on technology.even in mediacal.thus there is a need of
developing technology.
As civilization advances we depend more and more upon out inventions and
creations. we could live without them but not all of us. without the advances that we
have made in medicine, for example, many people would be dead and many others
would have much shorter lifespans. so, we have the ability to destroy the earth with
nuclear capabilities but we also have the ability to keep children alive who would
otherwise have died without the technology that we have learned to take for granted. .
People want what they want when they want it. They don't want something else, they
don't want less than they want, and they certainly don't want it at some other time.
Thus plays a major role in creating electropollution directly or indirectly.
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CHAPTER-3
EMF RADIATION SOURCES
Emf radiation sources cause electropollution. Life is full of electrical appliances.
Electricity is an inseparable part of our modern day society. This means that EMFs
will continue to be allaroundus. Aside from making our life easier, electricity might
also be making us sick.
Many buildings have a sick or imbalanced environment and cause their occupants to
feel tired,weak, anxious and sometimes depressed. This may be caused by
electromagnetic radiation EMF (as well as other toxic environmental situations).
If your home has high EMF readings, it is important to determine the sources of the
EMF so that remedial action can be taken (if possible).
FIG 3.1 RADIATION SOURCES
3.1 Radaiation Sources
EMFs radiate from all sides of the computer. Thus, you must not only be concerned
with sitting in front of the monitor but also if you are sitting near a computer or if a
computer is operating in a nearby room.Electric blankets and water-bed heaters create
a magnetic field that penetrates about 6-7 inches into the body (even when turned off).
Thus it is not surprising that an epidemiological study has linked electric blankets
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with miscarriages and childhood leukemia.Electric clocks have a very high magnetic
field, up to three feet away. If you are using a bedside clock, you are probably
sleeping in an EMF equivalent to that of a power line. Telephones can emit
surprisingly strong EMFs, especially from the handset. This is a problem because we
hold the telephone so close to our head. They emit strong fields that travel several
inches right into your brain
There are many types of EMF sources, such as alarm clocks too close to their bed,
sitting too close to a TV or computer, or using a cell phone and some other are the
following
Broadcast (TV / Radio) – kW in VHF / UHF
Portable phones (5 W in VHF / UHF range)
Pager / Cordless phone (< 1 Watt in VHF)
Microwave oven – source produces 2000W, but only 5 mW leaks out of the door
(2.4GHz)
Cellular phones operate in 800/1900MHz bands, Cell Towers power can be up to
25 W; phone can put out 0.5 W (800 MHz, 1900 MHz, 1700MHz, 2100 MHz)
Wireless LAN / WiFi (Access points power is <1W, PDA power is in Mw.
Satellite Communications 4 – 40 GHz
Microwave repeaters 4 – 80 GHz
Wireless Antennas and Routers
Powerlines
Compact flourescent light bulbs(CFL)
Hair Dryers
Computers or TV etc.
3.2 Microwave Radiations
Microwaves are higher-frequency waves lying roughly between radio and infrared
waves. They have a number of common applications, the most familiar of which is the
microwave or microwave oven used for cooking. In these kitchen devices,
microwaves are used to excite the water molecules in food, thus generating heat.
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Microwaves can easily penetrate nonmetal containers but generally cannot penetrate
metal. For this reason, food to be microwaved cannot be heated in metal containers.
High densities of microwave radiation (such as what is found in masers, or
"microwave lasers") are known to cause health problems such as burns, cataracts,
nervous-system damage, and sterility. Exposure to microwave radiation is usually
regulated; the U.S. government limits exposure to 10 milliwatts per square centimeter
or less. Microwave radiation refers to the radiating wave movement in which
microwave energy travels. Microwaves are electromagnetic rays with a frequency
range of 0.3 GHz to 300 GHz. They are found between the radiowaves and the
infrared waves in the electromagneticspectrum.Microwaves take a straight line path.
Like all electromagnetic waves, they do not require a medium to travel through. They
can pass through non-metal materials like plastic and glass, but get reflected off metal
surfaces.
Microwave Radiation Through Microwaveoven
Microwaves are absorbed by food, fruit, vegetables and other materials with high
water content, and produce heat. This is the operational principle on which microwave
kitchen appliances work. A microwave oven consists of a high voltage transformer, an
electron tube called magnetron, a wave guide fan and a cooking chamber. The
transformer passes electric energy to the magnetron and the magnetron converts this
electric energy into microwave radiation. The microwaves are reflected in the cooking
chamber and are absorbed by the food.
FIG 3.2 MICROWAVE OVEN
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As a result of the microwave absorption, the water molecules in the food begin to
vibrate. This molecular movement produces heat and the resultant heat cooks the
food. Foods that have higher concentrations of water molecules cook faster. In thicker
foods, the outer part is cooked by the microwaves and the inner part is cooked by
conduction of heat from the heated outer part. Concerns about microwaves turning
food radioactive are baseless. The radiation in microwave radiation refers to the way
in which microwaves move, not radioactivity. Microwaves are of a non-ionizing
character. They do not have the energy to cause chemical changes in substances as as
would happen in the case of radioactivity.
3.3 Power Transmission Lines
EMF is commonly associated with power lines. A person standing directly under a
high- voltage transmission line may feel a mild shock when touching something that
conducts electricity. These sensations are caused by the strong electric fields from the
high-voltage electricity in the lines. They occur only at close range because the
electric fields rapidly become weaker as the distance from the line increases.
FIG 3.3 POWER TRANSMISSION LINES
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The power transmission lines, you house electricity, and radio/microwave
transmissions create a subliminal state of constant stress that over time degrades the
immune system. A wide range of studies has documented the debilitating effects of
this electro-pollution induced stress on the immune system. Manmade EMFs also
paralyze the body's electrically based healing system. Many people are concerned
about potential adverse health effects. Much of the research about power lines and
potential health effects is inconclusive. Despite more than two decades of research to
determine whether elevated EMF exposure, principally to magnetic fields, is related
to an increased risk of childhood leukemia, there is still no definitive answerSome
scientists are coming to the conclusion that power line electromagnetic fields should
be classified as a "probable human carcinogen".
3.4 Mobile Phone Radiation
Mobile (or cellular) phones use electric power to receive and transmit signals through
a base station tower that is linked with other transmission towers. These signals are
usually around 900 MHz which is within the microwave range. Mobile phones and
telephone towers emit microwave radiation, which is in the radio frequency
radiation(RFR) part of the spectrum of electromagnetic waves.Mobile phones are a
unique source of RFR exposure because the power transmitter itself is held against the
head of the user. The concern in this case is whether RFR generated around the
antenna of the phone during use can cause health effects from absorption into the head
(or the body, if the phone is used while clipped to the belt, or in a pocket).
FIG 3.4 CELL PHONE RADIATION
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"Radio waves from mobile phones harm body cells and damage DNA"Cellular
telephones and effects on the brain: the head as an antenna and brain tissue as a radio
receiver.Headache and other neuropsychological symptoms occur in users of cellular
telephones, and controversy exists concerning risks for brain cancer. We hypothesize
these effects result from the head serving as an antenna and brain tissue as a radio
receiver. Brain cells and tissues demodulate the cell-phone's various frequencies from
the radio frequency carrier. Low audio frequencies in the ranges of alpha and beta
waves affect these waves and thereby influence brain function.The effect of
microwaves from a mobile phone has an impact on the stability of cells in the body.
The main effects are neurological, causing headaches, memory loss and also sleeping
disorders. Even a short exposure to electromagnetic fields emitted by mobile phones
has an effect on brain physiology.
3.5 Compact Fluorescent Llight Bulbs (CFL)
These are the new light bulbs many people are using to conserve power. But "CFL
and Fluorescent lights produce dangerously high EMFs They will soon be mandated
by the government as traditional light bulbs will be banned in 2014. So, with this new
CFL technology, most of us will have no alternative but to use these toxic, cancer-
causing, buzzing EMF polluters. The only alternative will be the more expensive LED
bulb which actually are the safest.
FIG 3.5 COMPACT FLOURSCENT BULBS
These new Compact Fluorescent Light bulbs (CFL) are notorious for generating a
high EMF field, higher than normal fluorescent lights. And,because you are more
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likely to be closer to CFL lamp, the exposure is even higher.It's important to
understand that these energy-saving bulbs produce EMF ofmuch higher intensity then
regular bulbs. Of course they do not radiate as much as a microwave, but you have
only one microwave at home and about 60 bulbs. Replacing all those bulbs with the
energy saving bulbs could turn your house into a total electromagnetism.Not only do
these types of light bulbs produce high levels of EMF, they generate a especially
potent and harmful type of EMF called "dirty EMF" which is even more toxic to the
human body than other forms of EMF radiation.
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CHAPTER-4
INTERACTION OF ELECTROMAGNETIC RADIATION WITH
BIOLOGICAL SYSTEM
A number of recent developments have resulted in renewed interest in and
concern among scientists and the general public about the biological effectsof
microwave and radiofrequency radiation exposure.The interaction of electropollution
with biological system is bio-electromagnetics. Human beings and all other living
creatures have their own electromagnetic energy balance. Because our 1st moments
on Earth, we have encountered external EMFs as part of the Energetic Continuum.
The planet is naturally webbed with simple EMFs that are interconnected with solar
activities such as solar flares and atmospheric events such as lightening.The Earth
itself has an iron core that generates a halo of electromagnetic energy, reaching far
beyond our atmosphere. All life on Earth has adapted to and existed in this natural
electromagnetic environment for millions of years.
But in the last century, we have radically altered our environment. We have saturated
the planet with potent human-made EMFs, the likes of which have by no means
before been recognized on Earth. These human-made fields have a different wave
form, coherence, and frequency than natural EMFs, and their effects on living
biological systems are only just beginning to be understood.
The human body is an electrically conducting fluid. Any fluctuating magnetic field in
this conducting fluid produces electric currents. Besides, each cell has its electric
potential which gets affected by this electric current - long term disruptive effects,
especially when combined with other ever increasing fields in our environment.
4.1Biological Effects
The most pronounced biological effect from RF and microwaves radiation is heating,
or thermal changes in the body. In its interaction with matter, RF energy may be
reflected (as in the case of metals), transmitted through a medium (such as glass) with
little energy loss, or be absorbed raising the temperature of the absorber. This
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increase in temperature can be attributed to two effects. Joule heating is due to ionic
currents induced by the electric fields that are set up in the absorber. These ionic
currents cause electrons to collide with molecules in tissue and resistance heating
results. The other effect is due to the interaction between polar molecules in the
absorber and high frequency electric fields. The polar molecules begin to oscillate
back and forth in an attempt to maintain proper alignment with the electric field.
These oscillations are resisted by other forces and this vibratory resistance is
converted into heat.
4.2 Absorption of Radiation
Absorption of RF radiation and thus heating of the body tissues depends on several
factors including wavelength and wave front characteristics. Frequencies greater than
10,000 MHz (10 GHz) are absorbed mostly in the outer skin.
Frequencies between 10,000 MHz and 2500 MHz penetrate more deeply (3mm to 2
cm) and at wavelengths of 2500 MHz to 1300 MHz, penetration and absorption are
sufficient enough to cause damage to internal organs by tissue heating. Therefore the
absorption and penetration depth of RF and microwaves in tissue appear to be inverse
functions of frequency.
Heat absorption will be greatest in tissues that have high water content, such as
muscle, with less heat absorption taking place in bone and fat.In the past most
biological effects have been related to the incident power density (mW/cm2).
However, the absorption of electromagnetic energy is strongly dependant on its
frequency, the geometry of the exposure situation and the dielectric properties of the
tissue. Because of these factors, biological effects are more properly related to the
absorbed energy defined as the specific absorption rate or SAR.
After reviewing a large body of biological data, several standards setting
organizations (e.g. ACGIH, IEEE/ANSI, ICNIRP, FCC, etc.) found that hazardous
bio effects in humans occurs at a whole body SAR exceeding 4 W/kg; to be
conservative, standards setting organizations use 1/10 of this value. For comparison
purposes, the resting metabolic rate in humans is on the order of 1 W/kg and 5 W/kg
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when engaging in strenuous activity such as running. The heart’s metabolic rate is 33
W/kg. The effectiveness of the circulatory system in redistributing thermal energy is
dependent upon the degree of vascularization in any tissue, but is generally adequate
to cope with varying metabolic rates in the human body.
4.3 Penetration of Radiation
Penetration is the inverse of attenuation. The amount of penetration depends on the
energy of the individual photons and the atomic number, density, and thickness of the
object, as illustrated below. The degree of penetration of EMF into the body, which
depends on the rate at which the energy of the radiation is absorbed. Gammas can be
very penetrating and can pass through thick barriers. Several feet of concrete would be
needed to stop some of the more energetic gammas. A natural gamma source found in
the environment (and in the human body) is 40K, an isotope of potassium.Neutrons are
also very penetrating. Some elements, like hydrogen, capture and scatter neutrons.
Water is commonly used as a neutron radiation shield. The probability of photons
interacting, especially with the photoelectric effect, is related to their energy.
Increasing photon energy generally decreases the probability of interactions
(attenuation) and, therefore, increases penetration. As a rule, high-energy photons are
more penetrating than low-energy photons, although there are limits and exceptions.
Thermal Effects and Nonthermal Effects
Thermal Effects
Blood flow eventually distributes excess heat throughout the body. Sweating starts
when the body becomes overheated and cools the body by evaporation. The additional
heat load that is imposed on the body due to RF absorption must be dissipated like any
other heat load, and can be a significant health concern. Body functions can be
impaired when its temperature reaches 102oF and fatal near 107 to 108 oF.
Temperature rise will be greatest in tissues that lack or have poor thermoregulatory
mechanisms such as high blood flow. Examples are the eyes and testes. “Hot spots”
between tissue interfaces due to non-uniform heating can also develop caused by
reflective wave reinforcement.
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Occcular Effect
Lens opacification sufficient to cause reduced or loss of vision is termed a cataract.
Animal studies have shown that the critical range of frequencies is from 800 to 10,000
MHz.Damage to the inside layer of the cornea may also occur resulting in corneal
damage and loss of sight. This may occur from continuous wave exposure or pulsed
exposure, and varying with time in animal studies.
Nonthermal Effects
Some animal studies have shown central nervous system effects, altered cell
membrane permeability, behavioral effects, and others. These bio effects are
attributed to mechanisms other than thermal, and are generally thought to be caused
by exposures less than 10 mW/cm2; however, they are not well understood or
documented.Some studies may hint to a link between RF exposure and an increased
risk of cancer but this is inconclusive.
RF/microwave workers complaints have been noted to include nervousness,
irritability, headache, depression, sleeplessness, and others.Immunological
Studies have shown positive immune system effects while other studies have shown
suppressed effect. The mechanisms are not well understood or documented.
In animal studies prolonged exposure or exposure to high RF levels may cause
testicular damage, or debilitated or stillborn offspring.
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CHAPTER-5
ISTROPHIC RADIATION MONITORING SYSTEM
Radiation exposure to humans can be broadly classified as internal and external
exposure. Sealed sources, which are unlikely to cause internalexposure, are used
almost exclusively in radiotherapy. This chapter deals with the monitoring of external
exposures.
External exposure monitoring refers to measuring:
Radiation levels in and around work areas.
Radiation levels around radiotherapy equipment or source containers.
Equivalent doses received by individuals working with radiation
Radiation monitoring is carried out:
To assess workplace conditions and individual exposures.
To ensure acceptably safe and satisfactory radiological conditions in
the workplace;
To keep records of monitoring, over a long period of time, for the
purposes of regulation or good practice.
Radiation monitoring instruments are used both for area monitoring and for individual
monitoring. The instruments used for measuring radiationlevels are referred to as area
survey meters (or area monitors) and theinstruments used for recording the equivalent
doses received by individuals working with radiation are referred to as personal
dosimeters(or individual dosimeters). All instruments must be calibrated in terms of
the appropriate quantities used in radiation protection. Depending upon the electronics
used, detectors can operate in a ‘pulse’mode or in the ‘mean level’ or current mode.
Proportional and GM counters are normally operated in the pulse mode.Owing to the
finite resolving time (the time required by the detector toregain its normal state after
registering a pulse), these detectors willsaturate at high intensity radiation fields.
Recommendations regarding dosimetric quantities and units in radiationprotection
dosimetry are set forth by the International Commission onRadiation Units and
Measurements (ICRU). The recommendations on thepractical application of these
quantities in radiation protection are establishedby the International Commission on
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Radiological Protection (ICRP). In practice, the term ‘weaklypenetrating’ radiation
usually applies to photons below 15 keV and to bradiation.For the purpose of area
monitoring, the ambient dose equivalent H*(d)and directional dose equivalent H¢
(d,W) are defined. They link the externalradiation field to the effective dose
equivalent in the ICRU sphere phantomat depth d, on a radius in a specified direction
W.For strongly penetrating radiation the depth d = 10 mm is used; theambient dose
equivalent is denoted as H*(10) and the directional doseequivalent as H¢(10,W). For
weakly penetrating radiation the ambient and directional doseequivalents in the skin
at d = 0.07 mm, H*(0.07) and H¢(0.07,W), arerelevant, and in the lens of the eye at d
= 3 mm, H*(3) and H¢(3,W), are relevant.The operational quantities are defined for
practical measurements bothfor area and individual monitoring.
These istrophic radiation monitoring system is comprised of a metering instrument
and,depending upon the application,one or more field sensitive probes.all probes and
meters ar interchangble.
5.1 Description of Model 8616 Meter
The Model 8616 is our full-feautered metering instrument.In addition to the basic
functions of range selection and battery test,the Model 8616 offers additional features
for functionality and opearator convience.the meter is large 4 inches wide,and easy to
read.zeroing is accomplished automatically by a single push button located on the
carrying handle provided.An audible power density alarm is included ,along with a
front panel control which the operator may use to set the alarm threshold any were
between 0 & 100% of the full scale meter reading.The max-Hold function enables the
meter to display the highest reading encountered during the survey and a chart
recorder
Output permits the creation of permanent records of survey results or the interface
with other equipment.Both the chartrecorder and alalrm outputs follow the real time
indication,independent of utilization of the Max-Hold function.system response time
is selectable between one and three seconds to suit the particular application.The
Model 8616 also includes built-in rechargeable batteries and recharger.The unit may
be operatyed from 117 or 230VAC,and will recharge the batteries while operating.The
meter will operate on the batteries for 40 hours on a charge,with a 3:1 charge ratio.
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The typical system shown in figure below is manufactured by Narada Microwave
corporation.huappauge,newyork
Fig 5.1 MODEL 8616 FRONT PANEL
5.2 Functional descriptionof front panel controls and indicators
METER: It indicates the level of r-f field in mW/cm^2 as sensed by the Istrophic
probe.
METER RESPONSE SWITCH: It provides means of selecting FAST or SLOW
meter response.
MODESWITCH: It selects either normal operation or Maximum hold mode.
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ALARM:It provides audio alarm to indicate when the present power density level is
exceeded.
ALARM CONTROL: It provides means of setting the percentage of full scale meter
reading at which the audio alarm will sound to alert the operator of power density
greater at present level.
RANGESWITCH: It provides means of selecting either Mw/cm^2 or percent of
standard.
PROBECONNECTOR: It provides for connection of isotrophic probe.
ZERO CONTROL: It provides for electrical adjustment of meter zero setting.
ZERO BUTTON: It provides for automatic electrical setting of matter.
RECORDER JACK: It provides for the connection of an external recorder & provides
3V full scale.
AC CABLE PLUG CONNECTOR:It provides for connection to 115/230 VAC
electrical power for battery charging.
5.3 Narda 8616 Radiation Monitoring System Features
3½" linear scale which covers a 13 dB dynamic range
Two response times are available by front panel selection. A slow response
time of 3 seconds in addition to a fast response (one second)
Max hold
Panel control allows an audible alarm to be set at any percentage of full scale
value
1000:1 (30 dB) dynamic range
Zero pushbutton mounted in the handle provides a means for fast and accurate
automatic zeroing of the meter
Removable mounting bracket
All 8600 series probes are interchangeable
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Table 5.1 Meter Specifications
Dynamic Range 30 dBPower or Field Strength Reading Ranges See chart aboveMeter Scales Linear, Marked 0-2 and 0-10Sensitivity Ranges Three, selected by front panel switchZero Control Front panel pushbutton Response Time including Meter 1 second (nominal) fast position
3 second (nominal) slow position Additional Features Maximum Hold Method of Operation
Recorder Output+3V nominal at full scale into minimum load of 1000W
Power Density AlarmAn adjustable audible alarm preset by panel control for a percentage of full scale
Battery Type 25 Volt Rechargeable nickel-cadmium Battery Use Time (Approx.) 40 hours; 3:1 use to charge timeSize 10" x 4¼" x 4" not including handleWeight 5.5 lb
Table 5.2 Probe Specifications
Probe Model Frequency Range Full Scale RangesRange of Measurement
8652 8662B
300kHz - 10MHz300kHz - 1GHz
2, 20 and 200mW/cm²
0.1 to 200 mW/cm²
8661 300kHz - 1GHz0.2, 2 and 20 mW/cm²
0.01 to 20 mW/cm²
8631 10MHz - 300MHz0.2, 2 and 20 mW/cm²
0.01 to 20 mW/cm²
8633 10MHz - 300MHz
1,10 and 100 mW/cm²
0.05 to 100 mW/cm²
8682 300kHz - 1.5GHz2, 20 and 200% ANSI RFPG
0.02 to 200% ANSI RFPG
8621D 300MHz - 40GHz0.2,2and20 mW/cm²
0.1 to 20 mW/cm²
8623D 300MHz- 40GHz
1, 10 and 100 mW/cm²
0.05 to 100 mW/cm²
5.4 Field Probes
1)Electric Field Probes
2)Magnetic Field Probes
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Electric Field Probes:
With variety of isotropic electromagnetic field probes, including the electric field
broadband models covering the frequency range 50 KHz-18 GHz, and selective one
for GSM 900-1900 MHz range.
MODEL 8621D
These model Highfrequency Isotropic probes provides flat,accurate electric field
equivalent power density measurements over the frequency range of 300MHz to
40Ghz. calibration points are provided over this range.
Model 8621D provides fullscale ranges of 0.2mW/cm^2,2.0Mw/cm^2 and
20Mw/cm^2
MODEL 8623D
These model Highfrequency Isotropic probes provides flat,accurate electric field
equivalent power density measurements over the frequency range of 300MHz to
40Ghz.14 calibration points are provided over this range.
Model 8621D provides fullscale ranges of 1.0mW/cm^2,10Mw/cm^2 and
100Mw/cm^2
MODEL 8661
These model 8661D Lowfrequency Isotropic probes provides flat frequency
response which permits accurate electric field equivalent power density
measurements over the frequency range of 300kHz to 1000Mhz.
Model 8661D provides fullscale ranges of 0.2mW/cm^2, 2.0Mw/cm^2 and
20Mw/cm^2.
MODEL 8662
These model 8662D Lowfrequency Isotropic probes provides fla frequency response
which permits accurate electric field equivalent power density measurements over the
frequency range of 300kHz to 1000Mhz..
Model 8662D provides fullscale ranges of 2.0mW/cm^2, 20mW/cm^2 and
200mW/cm^2.
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Magnetic Field Probes
For RF safety testing of magnetic fields there is probe PI-H1 covering the the
frequency range of most industrial and broadcast applications 500 KHz-50 MHz.
MODEL8631
These model 8631 Isotropic probes provides flat accurate magnetic field
equivalent power density measurements over the frequency range of 10 to
300Mhz..
Model 8631D provides fullscale ranges of 0.2mW/cm^2, 2mW/cm^2 and
10mW/cm^2.
MODEL8633
These model 8633 Isotropic probes provides flat accurate magnetic field
equivalent power density measurements over the frequency range of 10 to
300MHz..
Model 8633D provides fullscale ranges of 1mW/cm^2, 10mW/cm^2 and
100mW/cm^2.
MODEL8652
These model 8652 low frequency Isotropic probe has a flat frequency
response which permits accurate magnetic field equivalent power density
measurements over the frequency range of 300kHz to 10MHz.
Model 8652D provides fullscale ranges of 2mW/cm^2, 20mW/cm^2 and
200mW/cm^2.
MODEL8654
These model 8654 low frequency Isotropic probe has a flat frequency response
which permits accurate magnetic field equivalent power density measurements
over the frequency range of 300kHz to 10MHz.
Model 8654D provides fullscale ranges of 20mW/cm^2, 200mW/cm^2 and
2000mW/cm^2.
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5.5 General Information For Operation of Probes
If the isotrophic probe is very close to the radaiating source ,it should be oriented with
the axis of the handle in line with the direction of travel of suspected radiation(probe
towards the sorce).
Narada probes are calibrated in a freespace planewave.The models 8621 and 8623
high frequency probes covers the range of 0.3to 40GHz and measure the ‘E’field.
Models 8631 & 8633 lowfrequency probes cover the range of 10MHz to 300MHz
and five additional low frequency probes,model 8652,8654,8660,8661 and 8662B are
available.These probes will extend the frequency range of the system down to
300KHz.The model models 8652 and 8654 measure the magnetic field and cover the
frequency range of system up to 10MHz.The full scale equipment powerdensity for
the model 8661 is 20Mw/ cm2. The model 8662 electric field ANSI conformal probe
has a frequency range of 0.3MHz through 1500 MHz with a sensitivity characteristic
that is the reverse of C95.1-1982 ANSI radio frequency protection guide.Metering
when this probe is used with the 8616 is an percent of standard.The range decal and
selector knobe permit proper scaling at 200%,20% and 2% full scale of standard.
The meter scales are marked in power density and truly apply in free space condition
where the ratio of electric and magnetic field is 377 ohms.At present most
specifications for radaiation hazards use equivalent plane wave powerdensuty of
Mw/cm2.Narda probes are therefore calibrated for meter reading in mW/ cm2.Althogh
they measure the electric and magnetic field components.
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CHAPTER-6
THEORY OF OPERATION OF 8616 METER
6.1 Pre Operation-Model 8616 Meter:
1. Review all safety procedures before beginning a radaiation survey.
2. Connect the desired istrophic Probe to the meter by plugging the probe
cable into the connector and tightening the locking collar.
3. Set the METER RESPONSE switch to the FAST position.
4. Set the ALARM control to the 100% position.
5. Set the RANGE switch BAT TEST position.observe the meter indication
( it should read above TEST MIN mark on the meter face.If the meter
reads below TESTMIN connect charging line cord and battery.use to
charge ratio is 22.5:1.every 1 hour of charge time will allow 2.5 hours of
use and a fully charged battery will therefore permits a minimum
of 40 hours of use time.)
6. Set range switch to 20/100/200 Mw/cm2.
7. Depress the ZERO push button and hold for a “0” reading on the meter
scale.
8. Set the RANGE switch to the 2/10/20 Mw/cm2 position and press the
ZERO button for a “0” reading on meter scale.
9. Repeat ZERO operation 2/1/2 Mw/cm2.
10. Reset ALARM control to the desired threshold value.
11. Probe operation may be checked by using Model 8699 test source.Depress
switch on 8699 for generation of test field.
Note
when zeroing the meter,the isotrophic probe should be placed in a zero density area to
avoid stray power density pickup.If zero density area is not available,place the probe
in the carrying case and partially close the cover when zeroing.
Caution
The required charging power source voltage is indicated at the front panel line cord
connector.It will indicate 115 or 230.This must correspond to the line source
voltage.An internal charging switch may be reset to accommodate the available
sources.
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Warning
If meter cannot be zeroed,the isotrophic probe may be defective.do not use a defective
probe to measure potentially hazardous radiation areas.
6.2 Peak Power Rating
The Maximum peak power rating of Models of 8621,8661 and 8631 Istrophic
probes is 60W/cm2.The peak power ratings of models are 8623 & 8633
is 300W/m2 and 600W/cm2 for models 8652 and 8662B.The Maximum average power
density indication with Models 8621 & 8631 probes is 60W/cm2times the duty factor
and with models 8623 & 8633 probe is 300W/ cm2times the duty factor .when using
Models 8621,8661 and 8631 Isotrophic probes to make measurements where radar
dutyfactors are less than 0.00033,the full scale meter indication will exceed the
60W/cm2 maximum Power density.
Zero Drift
To minimize zero drift,allow approximately fifteen minutes of warm up time
when operating the meter on the most sensitive range
Operating Procedure:
Perform pre-operating procedures before attempting a radiation survey.
Always start to measure an unknown field as far from the source as
possible.This will insure the safety of operating personnel.
Slowly introduce the isotrophic probe into the unknownfield.Hold the probe
by its handle & point it towards the unit under test or radiating source.The
meter should be held away from the source.move the probe in a circular
motion in the area of radiation field.if location or direction of propagation is
not known,the probe axis is best held at 450 to the ground arm out
strectched.observe the meter reading.If the meter reading approaches full
scale,withdraw the isotrophic probe and set the range switch to the 20/100/200
position.
To insure maximum accuracy of meter reading,the probe should be rotated
about its axis and average of minimum and maximum readings obtained.
If the approximate power density of the field to be measured is not known,use
the probe that has highest power rating.
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6.3 Ac Operation
Model 8616 Meter may be operated continuously from a 115 or 230 volt,50 to 440 hz
powerline.The proper required voltage is indicated at the front panel AC charge
connector.If possible,the line cord should be kept out of radiation field.If this is not
possible,the cable should be oriented so that it is normal to the “E” electric field.to
change the required line voltage from one setting to the other proceed as follows:
Remove cover from unit by removing six screws at back of case.
Set the 115/230 V AC switch to the desired position
Loosen two scor fews holding AC INPUT CONNECTOR.place “FLAG”over
panel markings to indicate proper line voltage.
Connect the chargable cable to the AC power source
MAX HOLD mode operation(8616)
With the MODE switch in the MAX HOLD position,the meter will indicate and
retain the maximum value of power density that the probe has surveyed.This reading
will be retained until the ZERO push button is depressed.The drift rate for the MAX
HOLD mode is less than 0.3% of reading per minute.A MAX HOLD Reading will
retained with in 3% of its intial value after 10 minutes of elapsedtime.the recorded
output corresponds to meter indications & provides retained output voltage of 3 volts.
Meter Selection Response Selection(8616)
A front pannel selector switch permits operation of the meter with a slow or fast
response.In the SLOW position the meter will indicate 90% of the full scale value of a
field having a stem function characterstic approximately 3secs. .In the FAST position
the meter will indicate 90% of the full scale value of a field hacing a stem function
characterstic less than 1sec.The FAST position is recommended for all except the
most unusual situations.
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SIMPLIFIED BLOCKDIAGRAM
FIG 6.1 SIMPLIFIED BLOCK DIAGRAM
The figure is a simplied blockdiagram showing the principal circuits.The meter
consisits of a Decade Adjustable Feedback Circuit,Indicator and battery Circuits,and
Auto zero and maxhold circuit in the Model 8616.
Probe Sensing Device
The electromagnetic field being surveyed induces current in the thermoelectric
elements in the probe.A low level DC thermo electric voltage is generatetd and
transmited by resistive leads to the variable gain pre-amplifier.The gain setting of
these pre-amplifier is connected by cable to the meter.It Consists of thermocouple
element,resistive field shield,pre-amp,indicating meter model,high resistive
leadwires.Each probe contains three mutually perpendicular lossy probe elements and
provides a DC outsignal proportional to square of electric field strength tangential to
the element.The summation of the DC signals(from 3orthogonal probe elements)
provides a measure of total energy,or power density,independent of direction or
polarization of RF signals.Detectors for DC signal generation are thin film
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thermocouples thet provide true square law input.The DC signal is proportional to the
power disipiate in the thermocouple elements and the average density in the volume
whichathe elements are contained.
Fig 6.2 Sensing Probe
The pre-amplifier is located in the handle and connected to the lements by inflexible
monolithic leads.This prevents the cable from modulating the signal if it is flexed or
moved.A multiconductor shielded cable connects the pre-amp probe to the 8616
meter. This cable carries the pre-amp output,powersupply voltages and a correction
voltage which is apllied to the input of the amplifier to compensate for the zero
offset.The probes broadband characteristics are obtained by distributing resistive
thermocouple dipoles along the lengths over the range of frequencies within which the
probe is intended to operate.
Adjustable Gain Pre-Amplifier
Model 8616 consisits comprises a decade adjustable amplifier stable amplifier
U2,which drives both an alarm section and indicator circuits.The Adjustable Gain
Pre-Amp is a general-purpose digitizer and used in temperature sensors. The pre-
amplifier is an extremely low noise operational amplifier.
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Decade Adjustable Circuit
The Model 8616 comprises a decade adjustable feedback circuit and indicator circuits.
By front panel selection of RANGE switch,the gain of probe amplifier is changed in
decade steps.An internal potentiometer is set to provide the required meter indicator
accuracy.The ZERO control potentiometer provides a finr meter adjustment.these
decade adjustable circuit drives both an alarm section and indicator circuits.
6.6 Battery Test
The battery test circuit ensures tht the battery needs minimum operating
requirements.When front panel TEST switch S101 is set to BAT,front panel meter
M101 functions as a voltmeter and samples the battery voltage.A fully charged
battery will provide aminimum of 40 hours of continous use without recharge.The use
to charge ratio is 2.5:1 and a charge period of 1hour is therefore required for every 2.5
hours.
Indicator
The indicator circuit consisits of amplifiers U4,U5 and a meter.There are two modes
of operation:MAXHOLD and NORMAL.In the NORMAL mode switch S103 shorts
out CR11,U4 and U5 operate as linear cascaded amplifiers with a gain of 30.This
provides a recorder output as fullscale indication of 3 volts;minimum load resistance
for the recorder is 1K ohm.In this meter becomes the summing resistor of the
feedback network.
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CHAPTER-7
CRITICAL EXPOSURE LEVELS BY VARIOUS PROTECTION
STANDARDS
7.1 Critical exposure
Beyond exposed to these critical levels which are given by many protection
stanadards setting organisations(e.g. ACGIH, IEEE/ANSI, ICNIRP, FCC, etc.),may
cause many hazardous biological effects in livingsystem .The protection standards
setting organizations are
American National Standards Institute (ANSI)
American Conference of Governmental Industrial Hygienists
National Council on Radiation Protection (NCRP)
National Radiological protection Board(NRPB),UK
International Radiological Protection Association(IRPA)
Federal Communication Commision(FCC)
(all the above standards declared different exposure levels w.r.t to time of exposure
and frequency)
Purpose and Requirements
This guide will present a summary of the basics of radiofrequency (RF) and
microwave safety, biological effects, and exposure limits to be used at Cornell
University. Some recommendations are made that, if followed, would enhance the
safety of equipment. In other cases a particular item or action will be required.
1)Power Density per unit area, typically milliwatts/cm2 or watts/m2.
2)The electric and magnetic fields are perpendicular to each other, and do not vary
from point to point. Power density measurements are possible in the far field..
3) Power density (PD) = E x H V-A/m2 = watt/m2
4)Approximate PD can be found from:
PD = E2 / 3770 mW/cm2 or
PD = 37.7 x H25)Impedance of free space = 377 ohms.
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7.2 FCC (Federal ComMunication Commission)
Currently the FCC has adopted exposure limits from the National Council on
Radiation Protection (NCRP) and can be found in the federal regulations at 4CFR .
The FCC recommendations covers 300 kHz to 100 GHz and tables of FCC limits
Table 7.1 FCC exposure exposure limiting values
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Table 7.2 OCCUPATIONAL HEALTH AND SAFETY
ADMINISTRATION(OSHA)
OSHA requirements can be found in 29 CFR 1910.97 and covers the range of 10MHz
to 100 GHz
7.3 IEEE/ANSI Standard
The American National Standards Institute (ANSI) publishes recommended limits in
standard number IEEE/ANSI C95.1-2005 and covers the range of 100 kHz to 100
GHz.
Table 7.3 IEEE/ANSI C95.1-2005 Occupational Limits
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Table 7.4 IEEE/ANSI C95 Public exposure Limits
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7.4 ICNIRP recommendations
The International Commission on Non-Ionizing Radiation Protection
(ICNIRP) has issued guidelines for exposures from 100 kHz to 300 GHz in
Guidelines for Limiting Exposure to Time-Varying Electric, Magnetic, and
Electromagnetic Fields, 1998 (ICNIRP 1998).
Table 7.5 – ICNIRP Exposure Occupational Guidelines
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Table-7.6 ICNIRP Exposure Public Guideline
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7.7 Critical Exposure-Cellphones Rci Mesurement
20 V/m to 70 V/m with different make usage of cellphones suspended during flight
trials missiles.
RADIATION MEASUREMENT USING MONITORING SYSTEM:
Table 7.6 RCI radiation measurement
CELLPHONE TRANSMITTING
MODE(average peakvalue
in v/m)
RECEIVING MODE
(average peak value in
v/m)
X 30-55V/m 20 -70 V/m
Y 35-48V/m 46-60 V/m
Z 65-80 V/m 70-98 V/m
CHAPTER-8
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DAMAGING EFFECTS OF ELECTROPOLLUTION ON HUMAN HEALTH
Every benefit nature provides has some inherent risks of biological price which is
dangerous The effect of radiation on human health is the subject of recent interest and
study, as a result of the enormous increase in radiation sources usage throughout the
world. The world suffers from "electromagnetic contamination", "e-smog", or
"Electromagnetic pollution". The widespread use of technology that radiates EMF
(Electro-Magnetic Field), EMR (Electro-Magnetic Radiation), and ELF (Extremely
Low Frequency) constantly bombards the human body affecting its Biofield.EMF
Pollution may be the most significant form of pollution that human activity has
produced in this century,all the more dangerous because it is invisible and
insensible.” There is much controversy over the effects of electromagnetic fields
(EMF) on human health. One thing is certain, that the level of electro-pollution
(electro-magnetic fields) is at an all time high and rising, and coincidentally, so are
human diseases. many scientists, public health and public policy experts have
documented the scientific evidence on health impacts of exposure to electromagnetic
fields.
Just how EMFs affect humans is still not entirely known. Researchers are trying to
pinpoint ways in which EMFs might cause cells to grow and multiply abnormally
Power frequency electromagnetic fields induce biological effects. Visible and
ultraviolet frequencies cause pernicious damages to cells. Persistente exposure to sun
by a white man may cause skin cancer, as the ultraviolet radiation of sun rays has
cancer producing effect by damaging the genetic material, DNA.
Twenty percent of kidney transplant patient develop skin cancer within a decade.
AIDS patients also have a tendency to develop skin cancer. Above and below the
microwave and radio frequencies electromagnetic energy causes cancer.The radio
frequency (RF) stations caused change in T &B lymphocytic cells and reduced their
immunocompetence. The radar and other defence communication also cause damage
to human CNS.
8.1 Negative Effects of EMF Radiation on Our Health
Many scientists, public health and public policy experts have documented the
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scientific evidence on health impacts of exposure to electromagnetic fields. When the
body ages, lacks exercise and proper diet, the electro-pollution intensifies
vulnerability to all kinds of sickness and disease. Diseases linked to excessive
exposure to EMF include:
child leukemia brain tumors acoustic neuromas breast cancer diseases of the nervous system
Alzheimer’s disease Parkinson’s disease damage causes mutation and initiating cancer; effects on stress proteins weakens the stress proteins; effects on the immune system Immune dysfunction Chronic allergic responses Ill health Infertility Poor concentration Sleep disruption
Alzheimer's disease is a disease of the nervous system. There is strong evidence that long- term exposure to ELF is a risk factor for Alzheimer's disease.
8.2 Microwave damages
Microwaves can easily penetrate nonmetal containers but generally cannot penetrate
metal. For this reason, food to be microwaved cannot be heated in metal containers.
High densities of microwave radiation (such as what is found in masers, or
"microwave lasers") are known to cause health problems such as burns, cataracts,
nervous-system damage, and sterility. Exposure to microwave radiation is usually
regulated; the U.S. government limits exposure to 10 milliwatts per square centimeter
or less.
Radiation from Cell phones do definitely affect brainThe waves that emanate from the
Cell Phone affects the electrical activity of the Brain and in the longer run Brain may
be impaired.
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Harm our bloodcells Damage our DNA Cause nervecell damage Posiibly acelarate and contribute to onset of autism & trigger alzhemers’
disesase
Damage our eyes Lead to electromagnetic hypersensitivity Affect our heartrate & bloodpressure Chronic headaches Depression, Anxiety Sleep Disturbances Cancer ADHD High Blood Pressure Diabetes Fibromyalgia Effects cardiovascular system Hearing effects
8.3 Powerline damages:
Leukemia in children Braintumour Ill effects-cancer,congential malformations Neurodegeneration DNA damage-genetical disorders
8.4 Ecnomic Impact of EMF Radiation
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The economic victims of irresponsible application of radiation-based technology
include agriculture.Plants avoid high EMF levels by not growing as high as they
normally would; when the EMF source is removed, they grow normally. Cows are
also affected. As reported by Dr. Milham, when the “dirty electricity” in a U.S.
school was neutralized by Graham/Stetzer filters,“a dairy farmer a quarter of a
mile away noticed that his cows each gave an average of ten pounds more milk
per day, beginning the day the school installed its filters. The cows were
responding to dirty electricity being removed from the ground currents.”In 2008,
the French courtordered a power company to compensate cattle farmers for EMF
damage.Living creatures are electrical beings able to function only within
specificfrequencies. Devra Davis observes: “The difference between being alive
and being dead is just one thing - the presence of electrical activity in the brain.”
Thoracic surgeon, Dr. William Rae, co-founder of the American Academy
forEnvironmental Medicine with Linus Pauling and Dr. Theron Randolph,
originally became interested in environmental influences on health when
operating room equipment caused him to become seriously EMF-sensitive in the
1970s.
His research led him to recognize the deleterious influence of pesticides and many
other environmental toxins, all of which cause multi-system damage. The immune
system is the primary target, which does its job through electrically-charged
biological substances such as neurotransmitters, hormones, and peptides, which
transmit faster than the speed of light
It has been known since the 1990s that environmental illness from biological
and electrohypersensitivity share the process of a disastrous reduction in
cholinesterase, a nervous system enzyme. Its sudden depletion can cause
depression and suicidal behavior.
CHAPTER-9
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PREVENTIVE MEASURES AND NUTRITIONAL SUPPORT
9.1 Prevention Measures
The technological revolution continues to offer us great potential
improvement in the quality of our lives. In order to fully receive the positive gifts of
this technology, it is important that we identify and protect ourselves and our loved
ones from the negative effects this revolution is also having on us.Some preventive
measures should be taken to avoid from exposure of radaiation sources
Children Should Never Use Cell Phones: Barring a life-threatening
emergency, children should not use a cell phone, or a wireless device of any
type. Children are far more vulnerable to cell phone radiation than adults,
because of their thinner skull bones.
Don't use a cell phone any more than you have to. Don't use it inside buildings
or cars. Use it in open areas so the phone won't have to as hard to generate as
much power to get a good signal.
Don't talk on your cell phone when the signal bars are less than maximum.
This means your phone is working harder to maintain a signal. More power
means greater radiation exposure to you.
Don't let your kids use cell phones except in emergencies. The radiation
penetrates their head easier because their skull bones are softer. Their brains
are also in a development stage. That's not a good time to expose it to
radiation. They can live without one. You did, remember?
Don't use a cordless phone: They're three times worse than cell phones and
are a continual source of radiation in your home even when they aren't being
used. Go back to a landline phone.
Get rid of your wireless router. Again, this is a continual source of radiation
that is being beamed all over your house 24 hours a day, even while you sleep.
Go back to a hardwired cable connection. You won't get kicked off the
Internet near as often either. If you refuse to get rid of your wireless router at
least turn it off at night.
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Only purchase cell phones with a speakerphone function. Then use it!
Hands-free headsets are bad. The wires running around and across the head
will act as an "antenna" and will actually attract more radiation to the head,
making the problem worse. The exception here is a headset with an "airtube"
piece in it which gets the wires away from the head. They do help some but
don't think they are your security blanket.
Stand well back from appliances like microwave ovens when they are in
operation. The microwave oven is often the appliance that produces the
greatest amount of radiation in most homes. The second largest radiation-
producing device is the hairdryer.
Don't let your school install Wi-Fi in the classrooms and fight any decision
to install a cell phone tower on school property.
Don't live near a cell phone tower if you have any choice in this. Check the
quantity and locations of cell phone towers and antennas near your home by
going to Barring a life-threatening emergency, children should not use a cell
phone, or a wireless device of any type. Children are far more vulnerable to
cell phone radiation than adults, because of their thinner skull bones.
Reduce Your Cell Phone Use: Turn your cell phone off more often. Reserve
it for emergencies or important matters. As long as your cell phone is on, it
emits radiation intermittently, even when you are not actually making a call.
Use a Land Line at Home and at Work: Although more and more people
are switching to using cell phones as their exclusive phone contact, it is a
dangerous trend and you can choose to opt out of the madness.
Reduce or Eliminate Your Use of Other Wireless Devices: You would be
wise to cut down your use of these devices. Just as with cell phones, it is
important to ask yourself whether or not you really need to use them every
single time. If you must use a portable home phone, use the older kind that
operates at 900MHz. They are no safer during calls, but at least many of them
donot broadcast constantly even when no call is being made.
Alternatively you can be very careful with the base station placement as that
causes the bulk of the problem since it transmits signals 24/7, even when you
aren't talking. So if you can keep the base station at least three rooms away
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from where you spend most of your time, and especially your bedroom, they
may not be as damaging to your health.
Ideally it would be helpful to turn off your base station every night before you
go to bed.
But you can pretty much be sure your portable phone is a problem if the
technology is DECT, or digitally enhanced cordless technology.
Use Your Cell Phone Only Where Reception is Good: The weaker the
reception, the more power your phone must use to transmit, and the more
power it uses, the more radiation it emits, and the deeper the dangerous radio
waves penetrate into your body. Ideally, you should only use your phone with
full bars and good reception.
Also seek to avoid carrying your phone on your body as that merely
maximizes any potential exposure. Ideally put it in your purse or carrying bag.
Placing a cell phone in a shirt pocket over the heart is asking for trouble, as is
placing it in a man's pocket if he seeks to preserve his fertility.
Don't Assume One Cell Phone is Safer Than Another. There's no such thing as
a "safe" cell phone.
Keep Your Cell Phone Away From Your Body When it is On: The most
dangerous place to be, in terms of radiation exposure, is within about six
inches of the emitting antenna. You do not want any part of your body within
that area.
Respect Others Who are More Sensitive: Some people who have become
sensitive can feel the effects of others' cell phones in the same room, even
when it is on but not being used.
If you are in a meeting, on public transportation, in a courtroom or other
public places, such as a doctor's office, keep your cell phone turned off out of
consideration for the 'second hand radiation' effects. Children are also more
vulnerable, so please avoid using your cell phone near children.
Use Safer Headset Technology: Wired headsets will certainly allow you to
keep the cell phone farther away from your body. However, if a wired headset
is not well-shielded -- and most of them are not -- the wire itself acts as an
antenna attracting ambient information carrying radio waves and transmitting
radiation directly to your brain.
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Make sure that the wire used to transmit the signal to your ear is shielded.
The best kind of headset to use is a combination shielded wire and air-tube
headset. These operate like a stethoscope, transmitting the information to your
head as an actual sound wave; although there are wires that still must be
shielded, there is no wire that goes all the way up to your head.
9.2 Nutritional Support:
Take supplemental melatonin to counteract the suppression of pineal gland
secretion. I recommend 300 mcg to 3 mg every evening, half an hour before
bedtime.
Take supplemental vitamins C and E, which, according to early studies,
significantly decrease tissue damage caused by cell phones (August 2007,
Toxicology and Industrial Health). I recommend daily dosages of at least 1-2
grams of mineral buffered vitamin C (in divided doses) and 800 IU of vitamin
E.
Take honeybee propolis, a rich source of the potent free-radical scavenger and
antioxidant caffeic acid. In lab rat studies, caffeic acid significantly protected
against cell phone-induced damage to heart and kidney tissue (October 2005,
Toxicology and Industrial Health; August 2005, Molecular and Cellular
Biochemistry). I recommend 500-1,000 mg of propolis twice daily. I like YS
Organic Bee Farms Propolis, which is available at Vitacost..
Increase your intake of apples, turnips, radishes, cauliflower, bok choy,
arugula, kale, and cabbage, all of which are good sources of caffeic acid.
Take Ginkgo biloba. After seven days' exposure to cell phones, the oxidative
damage to brain tissue in control rats was significant, and their natural brain
tissue antioxidant levels were depleted. But in rats pretreated with Ginkgo
biloba, brain damage was prevented and natural brain antioxidant levels were
preserved (February 2004, Clinica Chimica Acta). I recommend 60-120 mg
daily.
Take supplemental zinc. It is known to protect against a cell membrane-
damaging process known as lipid peroxidation, which electropollution causes
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in brain tissue. In laboratory rats exposed to electropollution for five minutes
every other day for six months, plasma zinc levels significantly dropped . I
recommend 15 mg daily
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