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  1. 1. Kuldip Singh, Younis Muhammad / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 4, July-August 2012, pp.1645-1648 Study of the Effects of RF/MW Radiations on Humans Kuldip Singh*, Younis Muhammad** *M.Tech Student, Department of Mechanical Engineering. University College of Engineering, Punjabi University, Patiala (Punjab) ** Assitant Professor, Department of Mechanical Engineering. University College of Engineering, Punjabi University, Patiala (Punjab)ABSTRACT Electronic devices have become a veryimportant part of everyone’s life, as thesedevices give some benefits of use on the otherhand they are risky in their use. These devicesemit radiations which are harmful for thehuman beings as well as for the environment. Inthis paper we have discussed about the sourcesof electromagnetic radiations, tolerable level ofradiations, some effects that can be caused byelectromagnetic radiations and the effect on theenvironment. Also some precautions arediscussed which can reduce the effect ofradiations to some extent. At the end of thepaper we found out that the electromagneticradiations produced from cell phones,computers and related equipment, microwaveovens, radio and TV transmitters and otherelectrical and electronic appliances areanalogous to the cigarettes of 21th century. Figure.1 Electromagnetic Spectrum The Electromagnetic spectrum consists of allKeywords - EM Radiations, Electromagnetic frequency domains increasing in frequency fromspectrum, Electromagnetic radiations (EMR). lowest frequency(104) to highest frequency(1022)Electromagnetic pollution. through Radio wave, Radar, Microwave, Infrared, Ultraviolet, X-ray, Gamma rays .I. INTRODUCTION The various equipments which generate II. CLASSIFICATION:electromagnetic radiations such as wireless phones The Electromagnetic radiation can bevarious electrical equipments etc. have now classified into ionizing radiations and non-ionizingbecome a very important part of life. Life cannot be radiations, based on whether they are capable ofimagined without these equipments. These ionizing atoms and breaking covalent bonds. Ultraelectromagnetic devices have various uses in violet and higher frequencies, such as X-rays ordomestic, industries and medical technology. gamma rays are ionizing. These pose their ownInduction heating is used in industries, MRI and special hazards. Non-ionizing radiations areCT scan are used to find out the abnormal associated with two major potential hazards:conditions in human body and hyperthermia electrical and biological. Additionally, inducedtechnique is used to treat cancer and tumors. In electric current caused by radiation can generatespite of all usefulness the electromagnetic fields sparks and create a fire or explosive hazard. Theimpose a great danger to the human body . electromagnetic spectrum includes several differentElectromagnetic pollution (or EMF pollution) is a classes of radiation: low frequency, radio waves,term given to all the man made electromagnetic microwaves, infrared, visible light, ultraviolet light,fields (EMF) of various frequencies, which fill x-rays and gamma rays. Wave frequency is whathomes, workplaces and public space. differentiates one class of radiation from another. Figure 1 shows the electromagnetic spectrum [1]. Electromagnetic pollution is due to frequencies below (oscillating slower than) visible light waves. Of course, x-rays and gamma rays (which oscillate faster than visible light) are highly dangerous but homes and workplaces are not filled with these rays. Electromagnetic pollution is everywhere. 1645 | P a g e
  2. 2. Kuldip Singh, Younis Muhammad / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 4, July-August 2012, pp.1645-1648A. SOURCES OF ELECTROMAGNETIC/RADIO that is pulsed, has more harmful effects than an unWAVES RADIATIONS modulated, steady carrier. These so-called „windowHeres a short list of the main culprits: effects‟ greatly complicate any attempt to understand the relationship between a) Cell (and other mobile) phones electromagnetic radiation and health. [5][6] b) Computers and related equipments Some of the most known effects of c) Microwave ovens RF/MW radiations are given below: d) Radio and TV transmitters  Blood Brain Barrier e) Electrical and electronic appliances  DNA damage f) House-wiring  Risk to children g) High and low voltage power lines  Effect on skin h) Information Networks  Tinnitus and Ear damage i) Cars, Motor cycles, Buses, Trains, Aero  Effect on Eye/ melanoma. planes. Increase in cancer riskLevel of radiation that is safe: C. Biological Effect on environment: Various standards and guidelines havebeen developed by organizations and countries (1) Farm animals:over the past several decades. Safety factors are  Dairy cows – Decreased milk production,then incorporated to arrive at specific levels of spontaneous abortions, reproductive andexposure to provide sufficient protection for developmental problems, and Generalvarious segments of the population. Not all declines in overall health.standards and guidelines throughout the world have  Sheep, dogs, cats, rabbits living near baserecommended the same limits for exposure. This stations are also affected by EMphilosophy is inconsistent with the approach taken radiations.by most other standards-setting bodies which baselimits on levels where recognized hazards may (2) Birds:occur and then incorporate appropriate safety  Interfere with navigation, reproduction,margins to ensure adequate protection. thinning of egg shells. In the United States, although  In India and London - 75% fall sparrowthe Federal Government has never itself developed population due to EM radiation. SparrowsRF/MW exposure standards, the FCC has adopted are “Red List” of endangered avianand used recognized safety guidelines for species due to EM radiations.evaluating RF/MW environmental exposure since  Prolonged EM radiation exposure in1985. Federal health and safety agencies, such as pigeons, swans, white stork and rock dovethe Environmental Protection Agency (EPA), the reduces their immunity and causes manyFood and Drug Administration (FDA), the National diseases such as bird flu which in turnInstitute for Occupational Safety and Health affects the humans.(NIOSH) and the Occupational Safety and HealthAdministration (OSHA) have also been activelyinvolved in monitoring and investigating issuesrelated to RF/MW exposure. The Institute ofElectrical and Electronics Engineers (IEEE) and the III. SPECIFIC ABSORPTION RATE (SAR)National Council on Radiation Protection and AND CELL PHONE USE TIME LIMITMeasurements (NCRP).The ANSI committee on The specific absorption rate (SAR) is theRF exposure standards (Standards Coordinating rate at which radiation is absorbed by human body,Committee 28) became a committee of the IEEE, measured in units of watts per (w/kg) which isand revised its earlier standard and issued its own actually for 6 minutes. In has a safety margin of 3two-tiered standard that had been developed over a to 4, so a person should not use cell phone for moreperiod of several years The ANSI/IEEE standards than 18 to 24 minutes per day. This information ishave been widely used and cited and have served as not commonly known to Indian people.the basis for similar standards in the United Statesand in other countries[2].B. What biological effect can be caused byRF/MW radiations? There are studies showing frequency-specific biological effects, and studiesdemonstrating that a high frequency signalmodulated at certain low frequencies, or a signal 1646 | P a g e
  3. 3. Kuldip Singh, Younis Muhammad / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 4, July-August 2012, pp.1645-1648Cell phones and SAR value clothing thickness and coupling efficiency as a function of frequency is shown below Model SAR Output Manufactures (W/Kg) V 195 Motorola 1.6 Rival Motorola 1.59 Sony Ericsson Satio 1.56 Nokia E71X & X6 1.53 Curve 8330 BlackBerry 1.54 Samsung Blue earth 0.196 Figure: Comparison of transmission coefficient with and without clothing with no air gap between skin and exterior clothing[4]. S3650corby Samsung 0.75 The water content in the human tissue will influence the depth of energy penetration into the Sgh-g800 body. Millimeter-wave radiation is reported by Samsung 0.23 Gandhi and Riazi [4] to penetrate less than 2 mm into the body because of the "Debye relaxation of LG Rumor 1.51 the water molecules" in the tissue [4]. The Debye Effect was observed by a Dutch physicist named SAR is expressed in Watts per Peter Debye. He discovered that EM waves are Kilogram absorbed by a dielectric because of molecular dipoles present in the dielectric material. Water Current UK Standard = 1.0W/Kg molecules are essentially dipoles constructed from atoms of hydrogen and oxygen. Hence, these Current US Standard = 1.6W/Kg dielectrics are rich in molecular dipoles and are able to quickly absorb millimeter-wave radiation. High frequency radiation emission are not expectedA San Francisco Govt. has made it mandatory for to penetrate deeply into the human body [4]the industry to display SAR value for each phone(USA today 14 July, 2010) V. DEPTH OF PENETRATION Energy emitted in the millimeter-wave band is not li0)kely to penetrate to more the about 1IV. FACT OF CLOTHING or 2 mm into the tissue [4]. Essentially, PF/MW It is known that RF/MW radiated energy energy radiated at wavelengths less than 3will be absorbed by the tissue of the human body. centimeters will be captured in the outer skinThe depth of energy penetration into the tissue surface. RF/MW wavelengths from 3 to 10depends primarily on the wavelength of the centimeters will penetrate to a depth of about I toincident radiation and the water content of the 10 mm. The greatest depth of penetration into thetissue [3] [4].Clothing can act as an impedance body will occur at wavelengths between 25 to 200matching transformer for RF/MW radiation. In centimeters. At these wavelengths RF/MW radiated1986, Gandhi and Riazi [4] reported that the energy can directly affect internal body organs andcoupling efficiency of clothing may be as high as cause serious injury. The human body is reported to90-95 percent for incident radiation in the be transparent to RF/MW radiated energy emittedmillimeter-wave band. They determined that the at wavelengths greater than 200 centimeters. Also,thickness of the clothing and frequency of the at frequencies above 300 MHz it has been observedincident radiation are important factors in the that the depth of energy penetration fluctuatescoupling condition. The relationship between rapidly with changes in frequency. In general, the 1647 | P a g e
  4. 4. Kuldip Singh, Younis Muhammad / International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue 4, July-August 2012, pp.1645-1648depth of energy penetration into the body will portion of their huge profits for R&D ondecline as the frequency of the incident radiation eliminating the hazards posed by the EMincreases. At 10 GHz, the absorption of RF/MW Radiations. Only then people all over the worldenergy will be similar to IR radiation [3]. These will carry out research to come out with solution.figures were published by the U. S. Department ofHealth, Education and Welfare [3]. REFERENCES [1] Ali Zamanian and Cy Hardeman “EMVI. HOW WE CAN PROTECT OUR SELF radiation and human health” , July 2005.FROM EM POLLUTION. [2] Robert F. Cleveland, Jr.Jerry L. Ulcek  Cell phones with a lower specific “Questions and Answers about Biological absorption rate (SAR) should be used. Effects and Potential Hazards of That means SAR value of a cell phone Radiofrequency Electromagnetic Fields” must one of the most important criterion Aug 1999 . while buying a new Handset  Making and receiving the calls should be [3] The Industrial Environment – Its done quickly so that the radiation Evaluation & Control, U.S Department of exposure time is minimal. Health, Education & Welfare, pp. 371-  If a person cannot avoid talking for longer 372, 1973. durations on the cell phone then it is recommended to use a wired headset [4] Gandhi and A. Riazi, "Absorption of because a Bluetooth paired headset will Millimeter Waves by Human Beings and have its own EM radiation Envelope. its Biological Implications", IEEE  Stricter radiation norms must be enforced Transactions Microwave Theory and in India. This can only be done when Techniques, vol. MTT-34, pp. 228-235, people have the knowledge about the 1986. dangers of EM radiations.  Calls should not be made when the [5] Adey, W.R. “Tissue interactions with non- network Signal is low because the cell ionizing electromagnetic fields”. Physiol. phone emits more EM radiations to Rev.61:435-514 (1981). compensate for the low network signal.  Use of cell phones by the children should [6] Belyaev, I.Y. “Non-thermal Biological be discouraged otherwise it should be Effects of Microwaves”,Microwave limited to bare minimum. Review 11:13-2, 2005.  Mobile base stations should be located far away from residential areas. This can only be done by passing strict laws and safety norms.VII. CONCLUSION 1) After the study it can be concluded that the radiations from Mobile base station towers, cell phones, computers, laptops, TV & FM towers and microwave ovens etc are very harmful for us and can have adverse effect on human body depending on the intensity and frequency of the electrometric radiation. It is always a good idea to avoid the unnecessary exposure to electromagnetic fields whenever possible. This does not mean that we have to stop living near the towers. We all know that automobiles create air pollution. Instead of avoiding them we came up with unleaded petrol, CNG driven vehicles, and hybrid vehicles etc similarly the solution to avoid excess radiation is to use the radiation shield. 2) Mobile companies should not be in the denial mode and accept that radiation pose serious health problems. They should invest some 1648 | P a g e