I think the best solution would be to keep samples around in somewhat reachable parts. Occassionally, people will get sick, and learn that the signs mean danger

I think the best solution would be to keep samples around in somewhat reachable parts. Occassionally, people will get sick, and learn that the signs mean danger, without causing an accident of catastrophic proportions, and recognize the huge radiation signs that label the actual storage as ominous signs.