RADIATION

Presented by
37. Aarya Sawant
38. Janvi Sawant
39. Amol Shinde
40. Mahima Tandel
 WHAT IS RADIATION?
According to WHO, Radiation is energy that travels in the form of waves or particles
and is part of our everyday environment. People are exposed to radiation from
cosmic rays, as well as to radioactive materials found in the soil, water, food, air and
also inside the body.

Human-made radiation sources are widely used in medicine, industry, and research.
There are two types of radiation: ionizing and non-ionizing radiation.
 SOURCES OF EXPOSURE
Natural Man - Made

1. Cosmic rays 1. Medical and dental:

X-rays, radioisotopes
2.Environmental: a) Terrestrial 2. Occupational exposure
b) Atmospheric 3. Nuclear:
Radioactive fall-out
4. Miscellaneous:
3.Internal : Potassium-40
Radio-active dial watches, isotope
Carbon-14 tagged products, luminous markers
 NATURAL SOURCES
Radiation is a part of man's environment.
There are various natural sources of radiations around us.
Man is exposed to natural radiation from time immemorial.
Natural background radiation arises from 3 sources:
 COSMIC RAYS
The cosmic rays which originate in outer space are weakened
as they pass through the atmosphere.

At Ordinary living altitudes,their impact is about 35 mrad a

year.

At altitude above 20 km cosmic radiations become important.

it has been calculated that a commercial jet pilot receives
about 300 mrad per year from cosmic radiation.
 ENVIRONMENTAL
RADIATION
Terrestrial Radiation
Radioactive elements such as Thorium, Uranium, Radium, and an
isotope of Potassium ( K40) are present in man’s environment,
example, soil, rocks, buildings. It is estimated that man designs 50
mrad per year from terrestrial radiation.
Areas exist, e.g Kerala in India where are rock formations containing
uranium, it can be as high as 2000 mrad a year.
 Atmospheric radiation
The external radiation dose from the radioactive gases
Radon and Thoron in the atmosphere is rather small
about 2 mrad per year.
 INTERNAL RADIATION
Man is also subjected to internal radiation is from radioactive matter, stored
in the body tissues.
These radioactive include minor quantities of Uranium,Thorium and related
substances, and isotopes of Potassium(K40), Strontuim(Sr90) and
carbon(C14).
it inflicts about 25 mrad a year on the body as a whole, but maybe as high
as 70 or 80.
it is estimated that total natural radiation to which the average person is
subjected, comes to approximately 0.1 rad a year.
 MAN-MADE SOURCES
Man is exposed to artificial or man-made sources. These are:
1. X-RAYS
Greatest man-made source of radiation exposure to general
population at the present time is medical and dental x-rays.
Two groups are involved: 1) patients
2) Radiologists and Medical Technicians
The skin dose to the patient from a single x-ray film varies roughly from
0.02 to 3.0 radiations.
 Radioactive fallout :
1. Nuclear explosion is release a tremendous amount of energy in the
form of heat, life, ionising, radiation, and many radioactive substances,
the important being the isotopes of Carbon (C14), Iodine(131),
Cesium(Cs137) and Strontium(Sr90).

2.Cesium and Strontium are considered most important because they

are liberated in large amounts and remain radioactive for many years .

3.These radioactive particles released into atmosphere float down to the

Earth for some years afterwards, and because of the air currents, particles
are distributed fairly evenly over the whole human race.
 NUCLEAR EXPLOSION
Nuclear explosion is an explosion
that occurs as a result of rapid
release of energy from a high speed
nuclear reaction

These explosions produce high-level

of ionizing radiations, and
radioactive debris, which is harmful
to humans.
Nuclear explosion are also used in nuclear
weapons and nuclear testing to determine
effectiveness, yield, abilities of nuclear weapons
and to demonstrate the strength of the weapons

the explosion sites are selected on the basis of

following factors like the remoteness of area
isolation, flatter, minimal wind to control fallout
as well as considerations for military and
scientific purposes
 Key Events and Explosions:

Trinity Test (July 16, 1945): The first nuclear explosion, a plutonium
implosion device tested in Alamogordo, New Mexico.

Hiroshima and Nagasaki (August 6 & 9, 1945):The United States dropped

atomic bombs on these Japanese cities, resulting in immense casualties and
the end of World War II.

Castle Bravo (March 1, 1954): A U.S. nuclear test at Bikini Atoll, which
accidentally became the most powerful test conducted by the US, with a yield
of 15 megatons.

Tsar Bomba (October 30, 1961): The Soviet Union detonated the largest
nuclear weapon ever, a 58-megaton atmospheric nuclear weapon over
Novaya Zemlya island in the Arctic Ocean.
 These explosions are carried out in location, including
the atmospheric, underwater and underground
Sites:

1.Pokharan Test Range(Rajasthan): used for all the India’s

nuclear tests.

2. Nevada Test Site: A primary location for US nuclear

testing, including underground tests.

3. Semipalatinsk Test Site (Kazakhstan): A major site

for Soviet Union/ Russia nuclear testing, both atmospheric
and underground.
4. Christmas Island (Kiribati) : Used for early UK nuclear tests.

5. Lop Nur: The primary site for China's nuclear tests.

Pokharan Nuclear Site Nevada Test Site Semipalatinsk Test Site (Kazakhstan):

Christmas Island (Kiribati) Lop Nur:

 Miscellaneous
Some everyday appliances, example, TV sets,
luminous wrist watches are radioactive, but radiation
from the sources at present is too small to be
important.
THANK YOU
 RADIATION
TYPES OF RADIATIONS
RADIATION UNIT
APPLICATIONS OF RADIATION

PRESENTED BY: MAHIMA TANDEL.

ROLL NO. 40
 TYPES OF RADIATION
Ionizing Non -Ionizing
Radiation Radiation

UV Rays
a. Electromagnetic b. Corpuscular
Visible Light
Radiation Radiation Infrared radiation
Microwave
Radio Frequency Radiation
X- Rays , Gamma Rays Alpha Rays , Beta Rays ,
, Proton
 IONIZING RADIATION
It is a type of energy released by atoms in the form of EM
waves or particles .

These are the radiations which has ability to penetrate tissues

and deposits its energy within the tissues .

Two types of ionizing radiations :

a. Electromagnetic Radiations
b. Corpuscular radiations
 A. ELECTROMAGNETIC
RADIATION
It is form of energy which is generated when electrically
charged particle move through matter or vaccum .

Also produced by oscillating magnetic and electric

disturbance .

eg. X-Rays , Gamma Rays

X - Rays Manmade
: Deep penetrating
Short Wavelength
High Energy
Use to create image of inside of the body

Gamma Rays
Emitted spontaneously by radioactive elements
during their disintegration
Deep Penetrating
Short Wavelength
High Energy
Use in medical treatment & sterilization
 B. CORPUSCULAR
RADIATION

Also known as “ Particle Radiation “.

Emission of energy in the form of fast moving subatomic

particle such as alpha, beta, proton , electrons , neutrons ,etc.
 NON-IONIZING RADIATION
It is a “Low Energy Radiation”.

means - it doesn’t have enough energy to remove elctrons from

atoms or molecules unlike ionizing radiation .

characteristics : 1. No Ionization
2. longer Wavelength
3. Low Energy
 INCLUDE :
1. UV Rays : Emitted by the Sun And other sources such as tanning
beds , welding torch , etc.
2. Visible Light : Visible to Human Eyes , having Wavelength
approximately bet. 380 to 780 nm .
Visible light used in fibre optic communications, photography,
and
electronic devices.
3. Infrared Radiation : Heat radiation that’s invisible to Human
eye but can be felt as heat . Used in satellite imaging, weather
4. Microwave Radiation : used in communications, radio astronomy,
remote sensing, radar, and in cooking as well.
5. Radiowaves : For broadcasting, communication & wireless
networking.
6. Radio Frequency Energy : Use in Cell phones & other devices,
Wireless Technology, industrial and medical purposes.
 IONISING RADIATIONS NON-IONISING RADIATIONS

High Energy Less Energy Than Ionising Radiation

can not emit but excite elctron from ground level to

Emits electron or other particles from atoms
higher level

Shorter Wavelength Longer Wavelength

High Penetrating Power Low Penetrating Power

Eg. X- Rays , Gamma Rays , Alpha Rays , Beta Rays , Eg. UV Rays ,Visible Light ,Infrared radiation
Proton ,Microwave
Radio Frequency Radiation

Extremely Harmful Less Harmful than Ionising Radiation

Cause - Arrythmias , Headache , Digestive issues , sleep

Cause- Cancers , lymphoma , Leukemia
issues
 RADIATION UNIT

Activity of the radioactive material is the no. of nuclear

disintegration per unit of time .

Unit of Activity = Becquerel [Bq]

1 Bq = 1 disintegration per unit sec

 Potency of Radiation :
Measured in 3 Ways

1. Roentgen 2. Rad 3. Rem

Unit of exposure Unit of Absorption Dose product of

absorbed dose
& modfying
factors
As per New SI Units :

1 Roentgen = 2.58 × 10 ^-4

Roentgen Coulomb /Kg c/kg

Rad Gray (Gy) 1Rad = 0.01 Gy

Rem Sievert ( Sv) 1Sv = 100 Rems

 APPLICATIONS OF RADIATION

In Medicine Industry Others

Diagnostic Sterillization & Food Irradiation

imaging Disinfection Archaeology
Radiation Material Smoke dectator
Therapy Testing Navigation
Nuclear Thickeness beacons
Gauging Everday objects
Medicine
Electricity Astronomy
Generation Natural
radiation, etc.
A. Diagnostic Imaging
1. X- Rays : Diagnose fractures & other bone
injuries
Detecting foreign objects
Identifying tumor & other
conditions like lung diseases

2. Ultrasound :
High frequency sound waves used in
ultrasound imaging & therapy.
Medical iimaging - Obsterics, cardiology,
musculoskeletal, etc.
Therapy - Physical therapy, Occupational
therapy and cancer treatment.
3. CT Scan ( Computed Tomography)
Use X- rays & computer technology to produce detailed
image of body structure
Diagnose conditions such as - injuries, cancer, vascular
disease
Used to monitor progression of disease and effective of
disease
To guide procedures such as -Biopsies &Tumor.

4. MRI ( Magnetic Resonance Imaging)

Non invasive medical imaging technique that
uses strong magnetic fields & radiowaves .

Diagnose conditions such as joint &

musculoskeletal disorder, neurological
disorder, cancer, etc.
5. PET (Positron Emission Tomography) Scan
Use small amount of radioactive material to produce detailed
image of body's metabollic activity
Use in conditions such as- lymphoma, lung cancer, breast
cancer.
Neurological & cardiovascular disease
Bone Scan
 6. Radiation Therapy:

Common cancer treatment

Uses ionizing radiation to destroy the cancer cell,
preventing them from growing & spreading.

Goal : To target cancer cells

while minimizing damage to healthy tissue.
7. Nuclear Medicine :

Medical specialty that utilizes radiopharmaceutical to diagnose,

stage, treat & monitor the response to disease.
Focus on assesing organ function & early detection of disease.
Imaging technique in conditions such as - Thyroid, Cancer,
Infection, Cardiovascular imaging
B. Industry

Thickness Gauging

Sterilization & Disinfection

Material Testing Electricity Generation

 C. Other:

Smoke Detector
Archaeology
Food Irradiation

Everyday Objects Natural Radiation Navigation Beacons

THANK
YOU !
BIOLOGICAL EFFECTS OF RADIATION
 effects of radiation:-

1. Exposure to high dose of radiation over short period of time leads

to acute / short term effects.
2. Exposure to low dose of radiation over extended period of time
leads to chronic/long term effects.
3. Extreme high doses tend to kill cells causing organ damage. This in
turn cause whole body response called “ACUTE RADIATION
SYNDROME”.
ACUTE RADIATION SYNDROME :-
•A life threatening illness that occurs when the body is exposed
to a large dose of penetrating radiation over a short period of
t im e.
• ARS is divided into 3 main presentations-
1)Hematopoetic. 2) Gastrointestinal. 3)Neurovascular.
*Hematopoetic:-
-When 25 rad is absorbed by body.
-Anemia due to drop in no. of RBC.
-Infections due to low no. of WBC.
-Bleeding due to lack of platelets.
 *Gastrointestinal:- *Neurovascular:-
-600 to 3000 rad is absorbed. -3000 or more rad is absorbed.
-Symptoms include nausea, loss. -symptoms like dizziness,headache,
of appetite, vomiting and. Decreased level of conciousness
abdominal pain.
 IONIZING RADIATION:-

• Ionizing radiation shows effect in 2 types of action namely,

1) Direct action

2) Indirect action
• DNA, RNA & proteins are the common critical target for radiation exposure.
• Biological effects resulting from direct interaction of radiation with target sites is
called direct action.
• The interaction of free radicals with critical sites may also result in biological effects
which is called indirect action.
DIRECT & INDIRECT ACTION:-
 RADIATION DAMAGE TO DNA:-

•DNA is the largest and most important molecule for radiation damage.
•Radiation exposure to DNA gives 2 major effects namely,

1)Cross linking. 2)Strand break.

•The strand breaks may be,
1)Single strand break. 2)Double strand break.
•Double strand break is most important damage in DNA after radiation exposure.
•The interaction of 2 double strand break may lead to cell killing, carcinogenesis and
mutation.
Deterministic

Stochastic
CELLULAR EFFECTS OF RADIATION:-
BIOLOGICAL RESPONSE AS PER DOSE OF RADIATION:-

•< 5 rad - No immediate observable effects.

•5-50 rad - Slight blood changes may be detected.
•50-150 rad - Slight blood changes notes & symptoms like nausea, vomiting,
fatigue, etc.
•150-1100 rad - Severe blood changes and symptoms noted immediately.
•1100-2000 rad - Probability of death increases to 100% within 1-2 weeks.
•>2000 rad - Death is certain.
•>5000 rad. - CNS can no longer control body functions.
THANK
YOU !
Janvi Sawant
RADIATION PROTECTION
AND PREVENTION
By amol shinde
 Aim

Radiation protection aims to prevent or reduce the

harmful effects of ionizing radiation, which can cause
deterministic effects e.g., burns, cancer mutation
Susceptibility to radiation

The LD 50/30 ( the dose that kill 50%population in 30 days) is influenced by

the :
Source of radiation
Dose rate
The LD 50/30 of x rays for humans is 250-450Rad and 4-5 sievert (Sv)
Rad*... Is a unit of absorbed dose for any ionizing radiation.
Why it is necessary?

Exposure more than threshold level produces following

biological effects:
Somatic effect
Genetic effect
Teratogenic effect
Damage DNA
Protection and prevention

Radiation protection and prevention are overseen by international and

national bodies including :
International Commission on Radiological Protection (ICRP)
International Atomic Energy Agency (IAEA)
national regulatory agencies like the Atomic Energy Regulatory Board
(AERB) in India.
Alara
The guiding principle of radiation safety is “ALARA. “ ALARA
stands for “as low as reasonably achievable.”
ALARA means avoiding exposure to radiation
that does not have a direct effect to you, even if the dose is small.
To do this, you can use three basic protective measures in
radiation safety are
time, distance, and shielding.
Time

Time” refers to the amount of time you

spend near a radioactive source.
Minimize your time near a radioactive
source to only what it takes to get the
job done. If you are in an area where
radiation levels are elevated:
Distance

Distance” refers to how close you are to a

radioactive source. Maximize your distance
from a
radioactive source as much as you can. If you
increase your distance, you decrease your
dose.
Shielding

Radiation shielding involves using materials to reduce the

intensity of radiation by absorbing or attenuating it, protecting
people and equipment from harmful effects. Materials like lead,
concrete, and specialized alloys are used for different types of
radiation. Eg. Aluminium, lead concrete
Industrial level Medical level
Thank
you
Roll. 39