"Riding in space you get irradiated a little."
What kind of radiation is it? X-ray?
A little bit of everything, actually. Cosmic rays, neutrons, protons, gamma rays, electrons. Granted, the particles are mostly stopped by the hull, but the gammas and cosmic rays come zipping right through the exterior of the spacecraft. You'd need a few feet of lead or concrete to give real gamma protection.
Space travel is far from routine...