> The becquerel, or Bq, is the si unit of (radio)activity. It is also defined as one event per second.<p>Bq is not defined as "one event per second". One becquerel is defined "as the activity of a quantity of radioactive material in which one nucleus decays per second." <a href="https://en.wikipedia.org/wiki/Becquerel" rel="nofollow">https://en.wikipedia.org/wiki/Becquerel</a>