Some are antiquated units, but there are also very different sorts of measurements made. You can measure total energy, the biological effect depending on tissue, or total decays. There are a bunch of antiquated units still used, but many units are measuring different effects. Becquerel is measuring decays per second, and is the most fundamental, sievert is based upon biological impact, and gray is based on total exposure. Most have alternative units as well.
Latest Answers