Study of Basic Radiation Physics NEW

8/2/2019 Study of Basic Radiation Physics NEW

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Mentor: Presented By:Dr. RAJESH KUMAR KALINDI GOGIA

M.Tech (E.P.)

01340809711



Radiation

Radiation: The process of emittingenergy in the form of waves orparticles.

Where does radiation come from?Radiation is generally produced

when particles interact or decay.

A large contribution of the radiationon earth is from the sun (solar) orfrom radioactive isotopes of theelements (terrestrial).

Radiation is going through you atthis very moment!



2.5 mSv/y

Air 51%

Radon & Thoron

Manmade 13%

Natural 87%

Nuclear 0.1%



CLASSIFICATION OF RADIATION

Radiation

Ionizing

Directly ionizing (chargedparticles)electrons, protons, etc.

Indirectly ionizing (neutral particles)

photons, neutrons

Non-ionizing

Depending on the amount of Energy transferred,Radiation may be classified -Ionizing and Non-Ionizing Radiation



Electromagnetic Spectrum



Radiation & Dosimetric Quantities

Activity

Exposure

Absorbed dose

Equivalent dose

Effective Dose



Radiation Quantities



Exposure



Relationship between Exposure and Photon Concentration



Radiation units

SI unit

Curie (Ci)

Relationship

Activity

Exposure

Absorbed dose

Effective dose

Becquerel

Coulomb/kg

Gray (J/kg)

Sievert

Roentgen (R)

rad

rem

1 Ci = 3.7x1010 Bq

1 C/kg = 3876R

1 Gy = 100 rad

1 Sv = 100 rem

1 rem = 10mSv

Old unit

Equivalent dose Sievert rem1 Sv = 100 rem

1 rem = 10mSv



Radiation Dose Limit

A-L-A-R -A As Low As Reasonably Achievable.

It is a requirement of the agreement state (ADH) that all facilitiespossessing radioactive materials licenses to have a formal ALARA program . It is the policy of University of Arkansas at Little Rock tokeep this exposure as low as reasonablyachievable:

ALA R A concept is based on :

due to some risk, however small, exists from any radiation dose, alldoses should be kept ALARA.

Includes reducing both internal and external radiation dose

ALARA is the responsibility of all employees.



ALARA

Radionuclide's can enter thebody in four ways

inhalation

wounds absorption

ingestion



External Radiation Protection:

The Three Ba

sicR

ules

Time : Dose = Dose Rate x Time

Distance : The Inverse Square Law

Shielding: Radiation Energy

(1)Shield Density

(2)Shield Thickness



A n ALA R A principle is toreduce the time in a radiation field

100 200 300 mrem

100 mrem/hr 1 hour 2 hours 3 hours

ALARA



0 1 2 3 4

ft. ft. ft. ft. ft.

100 25 11 6 mrem/hr

Inverse

square1 1/4 1/9 1/16

A nother ALA R A principle is tomaximize the distance from source

ALARA



Proper uses of shielding

Permanent shielding.

Use shielded containments. Wear safety glasses/goggles to protect your

eyes from radiation, when applicable.

Temporary shielding (e.g., lead blankets orconcrete blocks) Only installed when proper procedures are used.

ALARA



General Handling Precautions

Protective Clothing-

lab coats, gloves, masks, eye protection, sealing tapes etc.

The Work Place-

Designate Clean area, A bsorbent paper, drip trays, locks, nofood items.

Manipulations of Radioactive Materials-

plan ahead, use minimum amounts, sealing tubes, reduce volatilization, proper monitoring, shielding, dosimeter, publicperception.



Applications of Radiation

Medical Diagnoses andTreatment-

Research Applications

Food Irradiation

X-radiation,

1. Radiographs

2. Fluoroscopy

3. CT scan

NuclearMedicine

Biological and Genetic research Agricultural research

Space research

Pharmaceutical research

Food treatment comparableto pasteurization

y Killspests/microorganisms without fooddegradation

y Controls sprouting

Does not make the foodradioactive



Consumer Products/

Safety and Security

Spacecraft Power Supply

Electric Power Generation

Small radioactive sourceshave provided heat and

electrical power for spaceprobes for decades

Radioactive power supplieshave allowed space craft toexplore the outer solarsystem, too far from the sunfor solar panels to beeffective

Nuclear Power supplies about20% of the countrys electricpower

Unlike fossil fuels, nuclearpower does not releasegreenhouse gasses

Self-powered Lighting in ExitSigns

Smoke Detection Equipment

Pharmaceutical Detection

Bomb/Weapons Detection

Scanning and SurveillanceEquipment

Theft Deterrent Systems



REFRENCES



THA NK YOU

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Study of Basic Radiation Physics NEW