What is the difference between irradiation and irradiance?

Answer 1

Radiation is emitted from something and travels from its point of origin to somewhere else.

When radiation hits something else (and is therefore stopped) the thing that has been hit is said to have been irradiated.

Thus a sunbather is undergoing irradiation by radiation emitted by the sun.

Answer 2

Radiance and spectral radiance are radiometric measures that describe the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle in a specified direction. They are used to characterize both emission from diffuse sources and reflection from diffuse surfaces. The SI unit of radiance is watts per steradian per square metre (W·sr-1·m-2). Irradiance, radiant emittance, and radiant exitance are radiometry terms for the power of electromagnetic radiation at a surface, per unit area. "Irradiance" is used when the electromagnetic radiation is incident on the surface. "Radiant exitance" or "radiant emittance" is used when the radiation is emerging from the surface. The SI units for all of these quantities are watts per square metre (W·m−2), while the cgs units are ergs per square centimeter per second (erg·cm−2·s−1, often used in astronomy). These quantities are sometimes called intensity, but this usage leads to confusion with radiant intensity, which has different units. All of these quantities characterize the total amount of radiation present, at all frequencies. It is also common to consider each frequency in the spectrum separately. When this is done for radiation incident on a surface, it is called spectral irradiance, and has SI units W·m−3, or commonly W·m−2·nm−1. If a point source radiates light uniformly in all directions and there is no absorption, then the irradiance drops off in proportion to the distance from the object squared, since the total power is constant and it is spread over an area that increases with the square of the distance from the source. From Wikipedia the Free Encyclopedia

Answer 3

Exposure to a radiation source outside your body is called irradiation. But if radaition source enters your body, or gets on your skin or clothesit is called contamination and you become contaminated.

Answer 4

Contamination involves radioactive material, like dust, moving from one place to another. If radioactive dust settles on your skin then we say your skin has been 'contaminated'. The radioactive nuclei in the dust give off radiation (like alpha or beta particles) all the time. When these hit your skin we say the skin has been 'irradiated'.

Answer 5

Pasteurization is a process of heating food products to kill disease causing organisms and

Irradiation is a process also called cold pasteurization that expose foods to radiation to kill contaminating organism and retard ripening and spoilage of fruit and vegetables.

Answer 6

IRRADIANCE= POWER (Wm2)

IRRADIATION= ENERGY ( Wh/m2)