Radiation units

• Activity is the rate at which a radiation source disintegrates, transforms, or decays per unit time. A small mass can have very high activity and vice versa.
  
• Activity is measured in Curie (Ci) or Becquerel (Bq)
  1 Bq = one nuclear disintegration per second (dps)
  1 Ci = 3.7 x 10^10 Bq = 3.7 x 10^10 dps