4. What is Radiation?
Radiation is the process of
emitting energy through a
medium or space in the form
of waves or particles
5. WAVES PARTICLES
What is Radiation?
Radiation is the process of emitting energy through a medium or space in the form
of waves or particles
6. WAVES PARTICLES
NON-IONISING IONISING
What is Radiation?
Radiation is the process of emitting energy through a medium or space in the form
of waves or particles
7. What is Ionizing Radiation?
Type of radiation that has sufficient energy to knock-out
electrons in atoms and molecules
electron
Ionizing radiation
11. Radiation Hazards
....neutrons, x-rays & gamma rays
are more hazardous for the
entire body..
....alpha & beta emitters are more
hazardous When they are
ingested or inhaled..
12. Sources of Ionising Radiation
• Radioactive materials
– Radioactive materials continuously emit
radiation
– Cannot be turned OFF
• Radiation emitting devices or
equipment (e.g. X-ray machines)
– Machines can be turned ON and OFF
– When turned OFF, no radiation is
emitted
13. Sources of Ionising Radiation
• Radioactive materials
– Radioactive materials continuously emit
radiation
– Cannot be turned OFF
• Radiation emitting devices or
equipment (e.g. X-ray machines)
– Machines can be turned ON and OFF
– When turned OFF, no radiation is
emitted
14. Radioactive Materials
• unstable atoms that DECAY by
emitting particles and/or
electromagnetic radiation
• Release of ENERGY
• decays to form a more stable
nuclide
• Results in the formation of new
elements
• There are about more than
2,000 unstable or radioactive
nuclides
15. Radioactive Materials
• The rate at which the is
radiation emitted is called the
activity
• Becquerel (Bq) OR Curie (Ci)
1 Bq = 1 disintegration per second (dps)
1 Ci = 3.7 x 1010 Bq
• Half-life
• The TIME taken for one half
the nuclei in the sample to
decay
16. Radioactive Materials
• The rate at which the is
radiation emitted is called the
activity
• Becquerel (Bq) OR Curie (Ci) Cs-137 ~ 30 years
I-131 ~ 8 days
1 Bq = 1 disintegration per second (dps) Sr-90 ~ 28 yrs
1 Ci = 3.7 x 1010 Bq
• Half-life
• The TIME taken for one half
the nuclei in the sample to
decay
30. Biological effects
• Biological effects on living cells
1. Cells experience DNA damage
that are detected & repaired
2. DNA damage not repaired and
causes cell death
3. Cell experiences DNA
mutation and may induce
cancer
32. Radiation Dose
Absorbed radiation dose (energy/mass) received by
the body taking into account the radiation sensitivity
of specific tissues and body organs
measure of the biological effect of a particular type of
radiation on organs or tissues
Sieverts ( Sv )
milliSv (mSv) = 1/1000 Sv
microSv (µSv) = 1/1,000,000 Sv
nanoSn (nSv) = 1/1,000,000,000 Sv
35. Radiation Doses Received (mSv)
0.4 - 1.5 one chest X-ray
0.1 Background (per hr), Red Forest Chernobyl Exclusion zone
1-3 Mammogram
3 US average annual natural background
10 natural background Kerala coast, India
dose limit for workers
50 Cranial CT scan
100 small increase in cancer risk dose limit for Fukushima NPP workers
250 - 1000 Temporary nausea, blood cell changes, sterility in males;
Nausea, fatigue, vomiting, blood cell changes, loss of appetite,
1000 - 3000 sterility in males, death possible
early death in 50% of those exposed, sterility and cataracts in
3000 - 6000 survivors
36. Radiation Doses Received (mSv)
0.4 - 1.5 one chest X-ray
0.1 Background (per hr), Red Forest Chernobyl Exclusion zone
1-3 Mammogram
3 US average annual natural background
10 natural background Kerala coast, India
dose limit for workers
50 Cranial CT scan
100 small increase in cancer risk dose limit for Fukushima NPP workers
250 - 1000 Temporary nausea, blood cell changes, sterility in males;
Nausea, fatigue, vomiting, blood cell changes, loss of appetite,
1000 - 3000 sterility in males, death possible
early death in 50% of those exposed, sterility and cataracts in
3000 - 6000 survivors
47. Radiation Controls
• Evacuation (maximizing distance)
• Sheltering (shielding, minimizing
inhalation)
• Restriction of food products in
affected areas (minimizing ingestion)
• Restriction in water intake in
affected areas (minimizing intake)
• Medical intervention (taking of pills)
• Radiation monitoring
48. Radiation Controls
NOT YET NECESSARY
IN THE PHILIPPINES
• Evacuation (maximizing distance)
• Sheltering (shielding, minimizing
inhalation)
• Restriction of food products in
AFFECTED AREAS IN JAPAN
affected areas (minimizing ingestion)
ARE LOCALIZED
• Restriction in water intake in
affected areas (minimizing intake)
• Medical intervention (taking of pills)
• Radiation monitoring
RADIATION MONITORING
IS ONGOING