The science behind the Durridge logo

When a radon atom (Radon-222) emits an alpha particle in alpha decay, the atom’s mass number decreases by four (to Polonium-218, to Lead-214, etc.) due to the loss of the four nucleons in the alpha particle. Our logo depicts the four nucleons (in red) of an alpha particle, which are about to be ejected (and “captured”) from a radon nucleus as it decays.