Radiation Dose is the amount of radiation energy absorbed by the body or exposure level of rays during the treatment. This doses are usually measured in mGy/mSv. There are four different but interrelated units for measuring radiation dose called radioactivity, exposure, absorbed dose, and dose equivalent. Radiation Dose is measured by dosimeter device.
Radiation dose is used to measure total amount of ionization that the quantity of radiation could produce in air which can be distinguished from the absorbed dose given in rads, which represents the energy absorbed from the radiation per gram of specified body tissue. Scientific unit of measurement for radiation dose, commonly referred to as effective dose, is the millisievert (mSv). Other radiation dose measurement units include rad, rem, roentgen, sievert, and gray. The effective dose or Radiation dose accounts for the relative sensitivities of the different tissues exposed. More importantly, it allows for quantification of risk and comparison to more familiar sources of exposure that range from natural background radiation to radiographic medical procedures.
High radiation dose containing radioactive materials decay and produce ionizing radiation, which has sufficient energy that could break some chemical bonds. Radiation dose in higher levels could result in cancer. Until now, there have been no firm results on safer levels of radiation were detected. But some studies say, 1 rem received in a short period or over a long period would be safe without any side-effects.