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Ionising and Non-ionising Radiation |
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Ionising radiation
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Non-ionising radiation
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- Ionising radiation contains a higher energy content and causes electrons to be released from the atoms or molecules it irradiates
- Examples of ionising radiation are alpha radiation, beta radiation, and gamma radiation
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- Non-ionising radiation has a lower energy content and cannot release electrons from the atoms or molecules it illuminates
- Examples of non-ionising radiation are radio waves, microwaves, and infrared
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The characteristics of alpha, beta, and gamma rays:
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Characteristics
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Alpha (α)
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Particle size
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Big
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Charge
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Positive
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Ionising power
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High
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Penetrating power
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Low
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Deflection by magnetic fields
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Deflection by an electric field
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Beta (β)
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Gamma (γ)
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Small
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None
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Negative
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Neutral
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Medium
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Low
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Medium
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High
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Sources of ionising radiation:
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Sources of ionising radiation are divided into natural sources and man-made sources
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Sources of natural ionising radiation include cosmic radiation and background radiation
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Cosmic radiation is radiation emitted continuously from outer space that can cause interference with weather and communication systems
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Background radiation is radiation that is present everywhere but the level varies due to solar radiation and the presence of radon-222 gas (radioactive gas in the air)
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Measured in microSievert units/hour (µSv/h)
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Nuclear test and nuclear accident at Chernobyl April 1986 is a source of man-made ionising radiation
Exposure to ionising radiation and safety measures:
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Radioactive effects
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Security measures
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- Destruction of cells or tissues in the body
- Genetic mutations that may cause tumor growth and cancer
- Infertility
- The skin burns and becomes blind
- Limb deformity and death for severe cases
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- Chopsticks should be used to hold and transfer radioactive sources
- Radioactive material should be stored in lead containers
- Workers in radioactive laboratories must wear radioactive warning badges and special protective clothing made of lead rubber
- Lead shields can be used to protect users from radioactive radiation
- Radioactive waste must be handled properly so that it is safer and does not cause environmental pollution
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