Physical Danger
The railroad safety inspector is primarily concerned with the safety of others, but that doesn't mean that your own safety gets sent down the rails. As the FRA's website makes clear, there are quite a few safety risks you're going to have to consider.
While the hazardous materials safety inspector is involved with the most obvious dangers, each of the specialties comes with its own set of negative outcomes. Signal electrics will malfunction, engines can explode, and structures sometimes just give out.
Besides those fun health and safety adventures, there are the issues that affect inspectors of all stripes. Rail yards aren't the softest places to fall on your face, and there's plenty for you to trip on.
All the crevices, gaps, and tight spaces in which you may find yourself will place stress on all the tender points of your body. Machinery has a tendency to remove your ability to count to ten with your hands if you're not careful, and the bigger machines might do a whole lot worse.