Nuclear Radiation

Alpha Radiation

• Form is a fast-moving particle

• External Exposure - Low Risk

• Internal Exposure - High Risk (Increases Risk Of Cancer)

• Alpha radiation can cause lung cancer when alpha emitters are inhaled.

• Alpha particles cannot penetrate most matter they encounter.

• The Greatest exposure to alpha radiation is inhaling radon and its decaying products.

Beta Radiation

• Form is a fast-moving particle.

• Long-term exposure can cause rare acute exposure and chronic health problems.

• Beta particles travel several feet in open air and are easily stopped by solid materials.

• When taken internally. beta emitters can cause tissue damage and cancer.

Gamma Radiation

• Form is photons

• Primary hazard during radiological emergencies

• Gamma rays travel at the speed of light and exist only as long as they have energy.

Latent Period: The time between exposure and development of cancer.

High Radiation Doses

• kill cells, tissues, and organs.

• Causes cancer, Acute Radiation Syndrome, and even death

• >50 rem

Low Radiation Doses

• Damage to cells

• Biologial effects are so small, that they are not mostly detected.

• Body repairs damage

• <50 rem

Common Units: Curie (CI), Rad, and Rem

SI Unit: becquerel (Bq), gray (Gy), and sievery (Sv)

Radiation Emission Measurement

1 bq = 1 nuclear decay/sec

1 curie (Ci) = 37×10^9 nuclear decays/sec

• These measurements are used to express the # of disintegration of radioactive atoms in a radioactive material over a period of time.

• The amount of radioactive materials released into the environment.

Dose Measurement

1 gray (Gy) = 1 J/kg

1 rad = 0.01 (Gy)

• Indicates radiation dose absorbed by living tissue

• Amount of energy deposited per unit of mass of human tissue

Biological Risk Measurement

• 1 sievert (Sv) = 1 J of radiation/kg

• 1 Sv = Gy

• rem = rad Q

• Measures biological risk and exposure to radiation

Radiation Weighting Factor (Q): The ability to transfer energy to the body

• 1 for photons

• 1 for electrons

• 2 for protons

• 20 for alpha particles, fission fragments, and heavy ions

• 2 to 20 for neutrons, depending on the energy level

Radiation Detection Instruments

Geiger Counter: a device used to measure radiation by detecting alpha/beta/gamma rays.

Scintillation Counter: a device used to measure radiation by measuring quantities of light emitted from a sensor.

Film Badge: A badge made of photographic film, which can be used to measure a worker’s exposure to radiation.

• a device used for monitoring individual cumulative exposure to ionizing radiation

Cloud Chamber: This is a particle detector used to detect radiation in a sealed chamber.