The doctor monitors the dosimeters....after exposure. Continued, or I suppose, cumulative exposure is what they are looking for, and at some time you may reach a limit. But you've got to wonder what happens with a one time "spike" exposure.

We carried hazmat and radioactive stuff too (different carrier). Depending on what it was it was way in back (60+ feet) but sometimes I'd find it up front, nestled right next to those Omaha Steak shipments.