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Non-Ionizing Radiation

Non-Ionizing Radiation. Jan Jakuš. Definition.

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Non-Ionizing Radiation

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  1. Non-Ionizing Radiation Jan Jakuš

  2. Definition Non-Ionizing radiationincludes all kinds of ele-ctromagnetic (elmg.) radiations with frequen-cies < 1015 Hz and wavelengths λ = 10-8 - 104 m. i.e. ultraviolet radiation UV- light,Visible light, Infrared radiation IR-light, Microwaves, Long ,Medium, Short, and Ultra-short radiowaves). These elmg. radiations never create electrically charged IONS (cations+ and anions-) when tar-geting atoms or molecules. γ-Rays X-raysUV VL IR R a d i o W a v e s J J I o n i z i ng N o n – I o n i z i n g

  3. 1. Ultraviolet Radiation (UV-Light) UV Lightis invisible radiation with λ = 100- 400 nm, Sources: natural (Sun), artificial (mercury lamps ) Classification: UVA- long wave,“black-tanning light“ λ = 315 - 400 nm UVB- medium wave,“inflamatory“λ = 280 - 315 nm UVC- short wave,“killing germs“λ = 100 - 280 nm (comes only from artificial sources) Earth is targeted from Sun by UVA (90%) and UVB (10%)lights. 90% of UVB is absorbed by O3 and O2 Ozone O3 andO2 lower the intensity of UVA and UVB lights and totally absorb UVC light Ozone holes- increase alevel of UV radiation!

  4. Ozone Hole-Depletion of Stratospheric O3

  5. Effects of UV Radiation on Human Body Skin:Erythema- „early red coloured skin inflam- mation“(appears after 2-3 hours) Tanning(delyed pigmentation, because production of melanine.( it starts approx. 24- 48 hours after expo- sure) Vitamine Dproduction Skin Aging(Wrinkles, Dry skin, Skin cancer- melanoma) Eye: Inflammation- Conjunctivitis, Pain, Cataract IMUNITY: increases.Overexposure- decreases

  6. UV-light: Penetration Through Skin

  7. Protection against UV- light overexposure • Avoid tanning newborns and small children • Avoid tanning between 10 a.m.- 2 p.m, when intensity of Sun light is the highest (in the Middle Europe) • Always take sunscreens- wear glasses with UVA and UVB factors, cover head by wide hats, protect body with summer dress, and use grease without perfums • SUNNSCREENS must contain both UV-A and UV B protecting factors (at least No 20 for level of Sun radiation in the Middle Europe) • Do not tann when taking remedies (e.g. antibiotics, sulfonamids, etc.) • Avoid visit solaria frequently - mainly persons with blond hairs and light coloured skin - do it with care! • Take in mind- skin has its own a„memory“ and re-members its burning by UV-light overexposure! • Burning of skin in childhood is very dangerous, lea-ding to cancer in adult age, as well ! • Take into account the Solar index

  8. 2. Mobile Communication- Ultra High Frequency (UHF) radiowaves • It is an electromagnetic (elmg.)radiation with frequencies btw. 300-3000 MHz, and λ = 1 - 0.1m • Is kind of non-ionizing radiation • Is used at TV and Mobile Transmissions • Mobile Phones work mostly under frequency 900 and 1800 MHz. • Mobile phone is smalltransceiver,periodically connecting by radiowaves with Basic Mobile Station (BMS are placed on the top of hills, on the roofs, etc.) • The intensity of electromagnetic radiation in a vicinity of BMS is very high and danger for body

  9. Effects of Mobile Radiowaves During calling elmg. radiation from mobile spre-ads to an environment as a radiosignal. The wea-ker is a received signal ( e.g. in car, train, or in buildings builded from steel and concrete)the higher is an intensity of emitted elmg. radiation. This radiation affects the head, ear, neck also the digits and hand of calling person on the side whe-re a phone is taken by hand.

  10. Absorbtion of Mobile Radiowaves by Body The depht of penetration of mobile radiation to tiss-ues is 1-2 cm (affecting mostly the brain structu-res). The index for Specific Rate of Absorbtion (SAR)for brain tissue was established. N= 1.6- 2.0 (W.kg-1) For a particular value of SAR in different types of phones see the box where the mobileis stored. The intensity of mobile radiation is low (2 W), howe-ver in brain,theintensity maybe add together (summated) above normal value of SAR.Thus,the effectsdepend both on an intensity of mobile elmg. radiation and a time of calling (exposure)

  11. Biological Effects of Mobile Radiowaves 1. ThermalEffects-passingthetissueradiowavescreateheat - temperaturewithinthebrainrisesup ( approx. 0.10 C during 12 min. timeofphonecall), and this, in turnmaydamagetheneurons. Disordersoftheoptic and cochlearnerveswerealsopublishedlately. Also a lowerproductionofhormonmelatoninewasfound. Subjectivelly, persons are complainted on : burning and itchingof skin witherythema, somefeelingofheat in theear, badconcentration, sleepingdisorders, etc. 2.Non ThermalEffects-to-datemechanismsare obscure, howeverscientistspresumepossibilityforappearanceofbraincancere.g. astrocytoma(withlocationatthesideofhead, thatisdirectlytouched by phone)

  12. How to use mobiles safely? • Buy only phones with SAR <1.6(W.kg-1):look for SAR number being placed on the box • Do not call when driving or travelling by train (i.e. avoid do make calls at all places with low signal !) • Do not call over 2 minutes, as well. Rather use „hands free“ set. • Do not touch the head with an antena • Do not allow to children ( at least till 6 years of age) to use and make calls from mobiles • In pacient with cardiostimulator (pacemaker) store the mobile in pocket at least 20 cmfrom pacemaker and heart (ussually on an oppo-site side of body)

  13. Thank You For Attention

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