Measuring radiation dosage

The 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. Because different tissues and organs have varying sensitivity to radiation exposure, the actual radiation risk to different parts of the body from an x ray procedure varies. The term effective dose is used when referring to the radiation risk averaged over the entire body.The effective 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.