Irradiation

Irradiation is a term used in the context of radiation, in which energy in the form of electromagnetic radiation or particles is transmitted through space and interacts with the materials it comes into contact with. This process can have different physical and biological effects depending on the type of radiation and the type of material it passes through.

There are different forms of irradiation:

Electromagnetic Irradiation: This is the transfer of energy in the form of electromagnetic radiation, which includes visible light, radio waves, microwaves, X-rays, and gamma rays.

Particle Irradiation: This form of irradiation involves the transfer of energy through particles such as neutrons, electrons, protons and alpha particles.

Irradiation can have different effects depending on the wavelength, energy and type of radiation:

Biological effects: Irradiation can affect living cells and tissues. In medicine, for example, radiotherapy is used to treat tumors.

Physical effects: Certain types of irradiation, such as ultrasound or laser radiation, can have physical effects such as heating tissues or removing material.

Detection and imaging: Some types of irradiation, such as X-rays, are used to diagnose and image the internal structures of objects such as human bodies or materials.

Sterilization and preservation: Irradiation is used to destroy microorganisms and extend the shelf life of foods and other materials.

Manufacturing and research: In various industries, irradiation is used to produce new materials, study the structure of materials, and for other scientific and technical purposes.

The physical unit of irradiation is expressed in units of absorbed radiation dose in material or living tissue. The main units for measuring irradiation are:

Gray (Gy): It is a unit of absorbed dose of ionizing radiation in substances. It is defined as 1 joule of absorbed energy per kilogram of weight. This unit is used to measure the absorbed dose of exclusively ionizing radiation.

Sievert (Sv): Unit of radiation dose equivalent. It is based on gray, but also takes into account the biological effects of different types of radiation. The equivalent dose indicates the effects of ionizing radiation on human health. The sievert is used to measure the total radiation dose, including biological effects.

In the context of lighting, irradiance can also be used to denote illumination - radiated energy per unit area. Specifically, for example, the units "mJ/cm²" are used to measure radiation energy per unit area (one square centimeter). Specifically, it is millijoules per square centimeter.
This unit is often used to express the absorbed dose of light (or other electromagnetic radiation) at the surface of a material. It is used in areas such as photochemistry, optical measurements and UV disinfection where it is important to determine the amount of energy delivered or absorbed per unit area.