What is a Dose of Radiation?
A “dose” is the amount of radiation energy deposited into the body. The more energy deposited into the body, the higher the dose.
- Sievert (or rem) is a unit of measure for radiation dose (1 Sievert = 1 rem)
- A chest X-ray is 0.08 miliSievert
- Coast to coast airplane roundtrip is 0.05 miliSievert
- CT scan (head and body) is 1.11 miliSieverts
- The radiation dose limit of a nuclear energy worker is 20 miliSieverts per year
- The radiation dose limit of a person who is not a nuclear energy worker is 1 miliSievert per year.
- Average dose to everyone from background radiation is 3 miliSieverts per year
- Stochastic Effects (Long-term chronic exposure to radiation)
- Concern of incorrectly repaired cells. It can disrupt the growth of cells at a molecular level and increasing the risk of cancer.
- Body can repair some cell damaged from chronic radiation exposures.
- Non-Stochastic Effects (Short-term acute exposure to high radiation field, 1 sievert or higher)
- Inhibits tissue functions: it can be temporary or permanent
- Un-repairable damaged cell
- Bone marrow, reproductive organs, and lymphoid tissue are the most radiosensitive
- Muscle, nerve, brain, and bone cells are the least radiosensitive