radiation sources

RADIATION

Radioactivity is a part of life is a part of our earth - it has existed all along.

Naturally occurring radioactive materials are present in its crust, the floors and walls and in the food we eat and drink. There are radioactive gases in the air we breathe.

Our own bodies - muscles, bones, and tissue contain radioactive elements.

Man is exposed to natural radiation arising from the earth as well as from outside the earth.

We also receive exposure from man-made radiation, such as X-rays, radiation used to diagnose diseases and for cancer therapy.

Nuclear power plants are also sources of the same

RADIATION SOURCES

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They are broadly classified into :

1. Natural sources

2. Man Made sources

NATURAL SOURCES

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COSMIC RADIATION

TERRESTIAL RADIATION

INTERNAL RADIATION

COSMIC RAYS

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Cosmic rays are atom fragments that rain down on the Earth from outside of the solar system. They blaze at the speed of light .

Hess discovered cosmic rays, charged subatomic particles that streak through space

They're thought to be atomic nuclei from the entire range of naturally occurring elements, though the vast majority appear to be protons (hydrogen nuclei).

The source of cosmic rays, however, has remained mysterious. Scientists aren't sure which cosmic phenomena are accelerating the particles to their fantastic speeds.

COSMIC RADIATION

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The sun and stars send a constant stream of cosmic radiation to

Earth, much like a steady drizzle of rain.

Differences in elevation, atmospheric conditions, and the Earth's

magnetic field can change the amount (or dose) of cosmic

radiation that we receive.

http://www.nrc.gov/reading-rm/basic-ref/glossary/cosmic-radiation.html

http://www.nrc.gov/reading-rm/basic-ref/glossary/dose.html

BAZINGA!!!!

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Tonight 12:30 am to 3:30 am cosmo rays entering

earth from mars. So switch off your mobile at night.

Don’t keep your cell with you & put it away while

you are sleeping because they are too much

dangerous rays: NASA informs BBC NEWS. Please

spread this news.

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Despite the claim in the message, there are several reasons to say that

this information is untrue.

First, Mars could not emit harmful radiation because it is not a star.

Cosmic rays are emitted by stars. i.e bodies that are undergoing

nuclear reactions that is fusion ( in sun) or fission (in nuclear reactors).

Mars is neither. It is a planet that just reflects sunlight. It cannot emit

cosmic radiation.

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The earth’s atmosphere is capable of taking care of these rays

The magnetosphere absorbs and protects us from the sun’s

harmful radiation. Whatever remains is too feeble to affect any thing as

far as earth.

***So, to anyone who will receive this kind of message,

please think it over and help educate others. Spreading

dubious warnings such as this is unlikely to help

anyone.

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TERRESTRIAL RADIATION

The ground beneath our feet

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The other major source of naturally occurring radiation is from

minerals and materials buried in the earth. Most common are

potassium-40, uranium-238, and thorium-232, which all have fairly

long half-lives.

Additionally, there are small quantities of shorter-lived materials, such

as radium-226, decay product of U-238, and radon-222 a product

of Ra-226.

Radon, being a gas, can become a problem in some houses and other

buildings, seeping in usually through cracks in solid foundations, and

accumulating in rooms with poor ventilation.


In addition, water contains small amounts of dissolved uranium and

thorium.

All organic matter (both plant and animal) contains radioactive carbon

and potassium.

Some of these materials are ingested with food and water, while others

(such as radon) are inhaled.

WHAT IS RADON?


Radon is a naturally occurring radioactive gas. It has no smell, colour

or taste. Radon is produced from the natural radioactive decay of

uranium, which is found in all rocks and soil. Radon can also be found

in water.

Radon escapes easily from the ground into the air, where it decays and

produces further radioactive particles.

As we breathe, the particles are deposited on the cells lining the

airways, where they can damage DNA and potentially cause lung

cancer.

RADON IN DRINKING WATER


In many countries, drinking water is obtained from groundwater

sources such as springs, wells and boreholes. These sources of water

normally have higher concentrations of radon than surface water from

reservoirs, rivers or lakes.

Normally, a higher radon dose is received from inhaling radon

compared with ingestion.

The "WHO guidelines for drinking water quality" (2011) recommend that

screening levels for radon in drinking-water be set on the basis of the

national reference level for radon in air.


INTERNAL RADIATION

INSIDE YOU !!!


All people have internal radiation, mainly from radioactive

potassium-40 and carbon-14 inside their bodies from birth and,

therefore, are sources of exposure to others.

The variation in dose from one person to another is not as great as

that associated with cosmic and terrestrial sources.

Potassium and Carbon in the DNA and cells of living things

contain a certain percentage of radioactive isotopes


FACTS


Unsuspected , Bananas, being naturally very high in potassium, consequently have a higher than usual amount of potassium-40, a radioactive isotope.

Also carrots and white potatoes, carry slightly lower levels of potassium-40.

Lima beans have almost 50% more potassium-40 than bananas, and also very small amounts of radon-224.

The food with the highest concentration of radioactive elements, in this case radium, is the Brazil nut.


Brazil nuts become radioactive, due to their root system taking up radium from the soil.

In all these foods, however, the levels are extremely low and not considered harmful, and almost none of the radioactive material consumed while eating any of them is retained in the body.

The fat content of the Brazil nuts would pose a health risk long before the radiation in them, for example.

Drinking milk of a cow who has ingested radioactivity through soil indirectly expose us to radioactivity

Eg Strontium-90 found in cow’s milk after Chernobyl

Man-Made Sources


Although all living things are exposed to natural background

radiation, exposure to man-made radiation sources differs for the

following groups:

Members of the Public

Occupationally Exposed Individuals (Workers)


Nuclear power is the most important as well as harmful man made

source of radiation .

In fact, due to the presence of radioactive Uranium and Thorium

in the fly ash from coal burning power plants give off more

radiation into the environment, typically, than a nuclear power

plant.

NUCLEAR ACCIDENTS

IN INDIA


Below is a list of leaks, fires and structural damages that

have occurred in India’s civilian nuclear power sector.

As the Department of Atomic Energy is not obliged to reveal

details of ongoings at these plants to the public, there may

be many other accidents that we do not know about.

April 2011 Fire alarms blare in the control room of the Kaiga

Generating Station in Karnataka. Comments by officials alternately

say there was no fire, that there was only smoke and no fire, and that

the fire was not in a sensitive area . Details from the AERB are

awaited.

November 2009 Fifty-five employees consume radioactive material

after tritiated water finds its way into the drinking water cooler in

Kaiga Generating Station. The NPCIL attributes the incident to “an

insider’s mischief ”


April 2003 Six tonnes leak of heavy water at reactor II of the Narora

Atomic Power Station (NAPS) in Uttar Pradesh .

January 2003 Failure of a valve in the Kalpakkam Atomic

Reprocessing Plant in Tamil Nadu results in the release of high-level

waste, exposing six workers to high doses of radiation . The leaking

area of the plant had no radiation monitors or mechanisms to detect

valve failure, which may have prevented the employees’ exposure.

May 2002 Tritiated water leaks from a downgraded heavy water

storage tank at Rajasthan Atomic Power Station (RAPS) 1&2 into a

common dyke area. An estimated 22.2 Curies of radioactivity is

released into the environment .


November 2001 A leak of 1.4 tonnes of heavy water at the NAPS I

reactor, resulting in one worker receiving an internal radiation dose of

18.49 mSv

March 1999 Somewhere between four and fourteen tonnes of heavy

water leaks from the pipes at Madras Atomic Power Station (MAPS) at

Kalpakkam, Tamil Nadu, during a test process.

May 1994 The inner surface of the containment dome of Unit I of

Kaiga Generating Station collapses (delaminates) while the plant is

under construction. Approximately 130 tonnes of concrete fall from a

height of nearly thirty metres , injuring fourteen workers. The dome

had already been completed forming the part of the reactor designed

to prevent escape of radioactive material into the environment in the

case of an accident.


February 1994 Helium gas and heavy water leak in Unit 1 of RAPS. The plant is shut down until March 1997

March 1993 Two blades of the turbine in NAPS Unit I break off, slicing through other blades and indirectly causing a raging fire, which catches onto leaked oil and spreads through the turbine building.

January 1992 Four tons of heavy water spilt at RAPS


December 1991 A leak from pipelines in the vicinity of CIRUS and

Dhruva research reactors at the Bhabha Atomic Research Centre

(BARC) in Trombay, Maharashtra, results in severe Cs-137 soil

contamination of thousands of times the acceptable limit.

July 1991 A contracted labourer mistakenly paints the walls of RAPS

with heavy water before applying a coat of whitewash. He also washed

his paintbrush, face and hands in the deuterated and tritiated water,

and has not been traced since

March 1991 Heavy water leak at MAPS takes four days to clean up

(20).

FAMOUS ACCIDENT


Cobalt-60 pencils, were improperly disposed of by a research

institution in violating national regulations for radiation protection

and safety of radioactive sources

These were sold to scrap dealers who dismantled the equipment. This

accident resulted in Radiation injuries and one death.

All five patients suffered from the haematological form of the acute

radiation syndrome .

While four patients exposed to LOWER DOSES survived with

intensive or supportive treatment, the patient with 3.1 Gy

EXPOSURE died due to acute respiratory distress syndrome and

multi-organ failure


The granite tops in our houses or offices contain appreciable amount

of uranium.

It is relatively weak and has very low impact on us

The varieties of vintage Fiesta ware (or any red glazed pottery from

the 40s-60s) used uranium for bright colours in the glaze.

Modern products use artificial dyes to achieve the same colours.

USEFULNESS


Authorities in charge of preventing the poaching of elephants for their

ivory have discovered that it’s possible to tell if the ivory is recently

poached, or “antique” based on the presence of these elements.

Since they are absorbed by the bones of living animals. So ivory that is

purported to be hundreds of years old, which contains elevated levels

of strontium-90, for example, will be able to be seized as illegal.

Carbon dating is also famous use.

X RAY scanners , medicinal use of radioactivity

CONTAMINATION


When the radioactive material is present where it should not be

present

Eg. Nuclear fallout from a bomb (the whole purpose of which

would be to disperse radioactive contaminant)

A lab worker splashing some of a radioactive solution on his/her

pants and taking them home.

Now it can be fixed or removed in some cases but if it gets into

metal recycle plant then it is almost impossible to remove it

Disposal of radioactive waste consists of reprocessing it for

commercial use

Sometimes the best solution is burying it in concrete, rock

Pripyat in Ukraine abandoned after the Chernobyl accident due to the

high amount of radioactive contamination


EXPOSED TO RADIATION MAKE US

RADIOACTIVE?


Exposure to radiation does not immediately make a person

radioactive.

NEUTRON is capable of directly causing other material to become

radioactive , found inside nuclear reactors .

CT Scans and other routine medical procedures expose someone to

radiation without leaving that person radioactive afterwards

However, the ingestion of radioactive material does make a person

radioactive, temporarily .


Between the short half-lives of the elements involved and the body’s natural means of disposing of many radioactive elements, a person’s individual radioactivity is usually short-lived.

However, certain types of contamination, depending on the isotopes involved and the availability of treatment, can become permanently deposited in a person’s organs or bones.

radiation sources

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