Säteilyeristys

Säteilyeristys, or radiation shielding, refers to the practice of reducing the intensity of ionizing radiation. This is achieved by placing a material between a source of radiation and an object or person. The effectiveness of radiation shielding depends on the type and energy of the radiation, as well as the properties of the shielding material. Different types of radiation, such as alpha, beta, gamma, and neutron radiation, require different shielding approaches.

Alpha particles are easily stopped by a thin layer of material, such as a sheet of paper or the outer layer of skin. Beta particles, which are more energetic electrons or positrons, can penetrate further and are typically shielded by a few millimeters of plastic or aluminum. Gamma rays and X-rays are highly penetrating electromagnetic radiation and require denser materials like lead or concrete for effective shielding. Neutron radiation, which consists of subatomic particles, is particularly challenging to shield and often requires materials rich in hydrogen, such as water or polyethylene, followed by materials that absorb thermal neutrons.

The thickness and density of the shielding material are crucial factors. A thicker or denser material will absorb more radiation. In practical applications, radiation shielding is employed in various settings, including nuclear power plants, medical facilities for diagnostic imaging and radiation therapy, research laboratories, and in space exploration to protect astronauts from cosmic rays. The design of radiation shielding systems aims to achieve a balance between the required level of protection and practical considerations such as weight, cost, and space.