EM Fields and Wave Effect on Living being

Özgün Aydemir

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What is EM field?EM fields and waves are exist everywhere where

are electrical current

Direct current causes EM field and alternative current causes EM waves due to change in time.

Coverage of the EM waves are related to amplitude and the frequency of current.

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EM Fields on Daily BasisAnything carries current in it causes EM fields,

such as: cables, electrical/electronical gadgets, TV, radio antennas, mobile phones, satellite antennas

To look more specific, we can look devices that are used in home, such as: washing machine, dish washer, fridge, microwave oven, electrical heating tools, computers…

All these devices causes EM field around themselves

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EM radiation table for some of the devices we may use for daily bases:

DEVICE EM field Intensity (V/m)

Electric blanket 250

Kettle 130

Stereo 50

Fridge 60

Iron 60

Mixer 50

Toaster 40

Hair Drier 40

TV 30

Vacuum cleaner 165

EM Field effects on living being

The people who work near by high-voltage transmission lines, electricity poles, substations and in such kind of places were complaining about headaches, fatigue, loss of appetite, nausea and such kind of ailments.

Firstly, Russian doctors have discovered the bad influence of EM fields in mid-1960s

EM wave effects on muscles and nerves are observed on viruses, plants, bugs, birds and frogs

Collected data has proved that biological effect of EM waves are proportional to frequency of the wave.

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This awareness about the dangers of EM

waves have led scientists to research and that has provided important evidence to be obtained.

EM field effect on living being can be observed under two topics

Direct Effect

Indirect Effect7

Direct Effect: The case that body is exposed to EM field directly

Indirect Effect: It is a result of interaction of body with the objects which have different electrical potential.

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EM Radiation Spread along a straight line in space.Speed is equal to the speed of light. They transfer energy to the

environment proportional to frequency. EM energy is reduced due to

absorption and scattering when passing through articles. In the cavity EM energy is inversely proportional to the square of the distance.

Electromagnetic radiation can be divided in two groups that are ionizing radiation and non-ionizing radiation.

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.Ionizing radiation

Ionization is detached electrons from atoms and molecules.

Highly energy loaded EM waves might spare electrons from objects while having connection.

Yüksek frekanslı ve dolayısıyla yüksek enerjili olan x ışınları ve gama ışınları iyonlaştırıcı radyasyonlardır.

High-frequency and high-energy x-rays and gamma rays can be considered as ionizing radiation.

They can cause changes in biological tissues that comprises DNA and genetic material.

. Non-Ionizing Radiation

They are not as powerful as ionizing radiation, since they do not have such high energy

Radio waves, microwaves, IR, UV and visible light can be considered as non-ionizing radiation

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Non-Ionizing devices

Power transmission lines and transformer stations

Electric trainsTVComputer screens, Induction furnaces and

induction welding machines

Radio, TV and radio antennas of the transmitting station

Radar systems (continuous and pulsed)

Satellite communication systems

Electrical devices used in medicine

Microwave ovens

GSM communication system (basic mobile phone base station antennas and antenna)

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Non Ionizing radiation effect can be observed under two titles

Non-Heating Effect

Heating Effect

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Heating Effects

The electromagnetic energy absorbed by the body and body temperature increases.

The cause temperature rise of RF sources such as mobile phones is actually low. Long term effect of this effect is still on research.

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Non Heating effectsDepending on the non-heating effects of RF

waves are claimed to be effective for disorders and diseases of changes in brain activity, sleep disorders, attention disorders, headaches are available.

These risks are possible in case of very high experimental doses and durations. They are not valid for use as mobile phones.

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SAR (SPECIFIC ABSORBTION RATE)

SAR is absorption of electromagnetic energy by the body tissue. Unit of SAR is W / kg.

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To increase one degree of temperature on human body, 4W shall be absorbed per kg of tissue.

SAR limitation for living environment are settled to 0.08 W/kg which is 1/50 of this value

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Protection from EM waves

Turn off the electrical devices that are not used. Stand by mode will still keep having EM radiation.

Try to use low SAR devices. For computer screen, screen filters might be good idea to use

Better not to have TV and radio in bedroom

Switch off mobile phone when it’s not useful and try to use earphone during the phone calls

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StandartsETSI (European Telecommunication

Standardization Institute), in EU, FCC (Federal Communication Commission), in USA gives the standards for SAR levels.

ICNIRP (International Commission on Non-Ionizing Radiation Protection) gives the international standards.

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StandartsIn Europe, SAR limit is nearly 2 W/kg.

In USA, SAR limit is 1.6 W/kg.

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THANK YOU

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Q&A

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