Qualifications
A nuclear materials courier is a federal job, and federal jobs are typically pretty competitive. If the highlight of your résumé is your brief stint as a yoga instructor, you may want to rethink this position. To qualify for a nuclear materials courier, it's all about experience, experience, experience. Kind of like real estate, except...not.
There aren't any educational requirements for this job (sound the bells and whistles), but as a federal position, there are definitely what they call "specialized experience requirements." All federal positions work on a ranking scale, and to qualify to become a nuclear materials courier, you must be at least a GS-7 on the ranking scale when applying.
That sounds a lot scarier than it is. Basically, to qualify as a GS-7 you need at least one year of previous "specialized experience," either in the federal government or in a position similar to what a nuclear materials courier does (source).
Some examples of specialized experience could be having served in the military, working for the armed forces, or any high-risk, armed security work. (No, being a mall cop doesn't count.) It's important that you're able to show that you have at least one year's experience working on an armed tactical team in which you were responsible for protecting something or someone against the bad guys.
Think security patrols, convoy operations, and rapid force operations environments (source). You know those armored trucks that the banks use to transport their money? There's your year of experience right there. Thank us later.
Considering the word courier is in the job title, all qualifying applicants must have a valid U.S. driver's license and a squeaky-clean driving record. There's also that pesky age requirement, which mandates applicants to be between the ages of twenty-one and thirty-seven at the time of application. So if you're fresh out of high school, take some time and get some more of that specialized experience before applying.