Physical Danger
Driving a motor vehicle can be dangerous. Automobile fatalities are one of the leading causes of accidental deaths (source). As a DMV employee, that means getting to and from work is the most dangerous part of your job.
Most of the positions available at the DMV are danger-free careers. There isn't a whole lot of danger filing paperwork and conducting exams in a one-floor government building. Customers may get angry, but they usually won't resort to fisticuffs. On the off-chance they do, you'll have an armed guard making sure the situation is resolved quickly and, if necessary, with a Taser.
One position that does have a higher level of danger is that of DMV investigator. Not only do you leave the office and go on-site, you're actually an officer of the law with the ability to make arrests (source). Thankfully, you're going to be trained to handle this much greater risk, and you'll have your own firearm too. Just don't let any of the front desk employees get ahold of it.