Physics – 5.2.5 Safety precautions | e-Consult
5.2.5 Safety precautions (1 questions)
Alpha, beta, and gamma radiation are three different types of ionising radiation, each with distinct properties regarding their penetrating power and the shielding required to stop them. Here's a comparison:
| Radiation Type | Penetrating Power | Shielding Required |
| Alpha (α) | Low. Can be stopped by a sheet of paper or even the outer layer of skin. | Paper, skin. |
| Beta (β) | Medium. Can be stopped by a few millimetres of aluminium. | Aluminium, plastic. |
| Gamma (γ) | High. Requires thick layers of lead or concrete to be significantly attenuated. | Lead, concrete. |
Alpha particles are relatively heavy and positively charged. Their low penetrating power is due to their high charge and mass, which cause them to interact strongly with matter. They are easily stopped by a thin barrier like paper or the outer layer of skin.
Beta particles are electrons or positrons. They are lighter and less charged than alpha particles, giving them a greater penetrating power. Beta particles can be stopped by a few millimetres of aluminium or plastic.
Gamma rays are high-energy photons and have the highest penetrating power. They are uncharged and do not interact strongly with matter. To stop gamma rays, thick layers of lead or concrete are required.