Brief Answer:
shielding

Detailed Answer:
Hi

Ionizing radiation is a type of energy released by atoms that travels in the form of electromagnetic waves (gamma or X-rays) or particles (neutrons, beta or alpha). The spontaneous disintegration of atoms is called radioactivity, and the excess energy emitted is a form of ionizing radiation. Unstable elements which disintegrate and emit ionizing radiation are called radionuclides.

The administration of non radioactive iodine can prevent the uptake of radioactive iodine by the thyroid gland. When potassium iodide (KI) pills are taken before or shortly after exposure, they saturate the thyroid gland to reduce the dose and risk of thyroid cancer. KI pills do not protect against external radiation, or against any other radioactive substances apart from radioactive iodine

Another way to minimize the amount of radiation and stay away from it is to put some material, called shielding, between the radiation source and people. When the radiation strikes the shielding, it begins to create ions in the shield. Each time an ion is created, the radiation uses some of its energy. If the shield is thick enough, the radiation will use up its energy before it gets through the shield.

Any material provides some shielding. Common shielding materials are steel (iron), concrete, lead, and soil. Scientists measure the shielding ability of a material by determining the thickness of the material required to absorb half of the radiation from a given source. This thickness of the material is called the half-thickness. Radiation that has passed through one half-thickness will be reduced by half again if it passes through another half-thickness. The half-thickness depends on both the characteristics of the shielding material and type and energy of the radiation being emitted.

Regards

DR DE

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