Physical Danger
Let's look at this realistically. Most of your social worker career will be spent in meetings, on the phone, and writing endless reports for your higher-ups. We also can't forget the piles of forms you have to complete for the insurance companies.
While you're sitting in yet another mid-afternoon meeting, you could fall asleep and crash onto the floor, possibly banging your knee on someone else's chair. You could spend so much time on the phone that your neck permanently freezes into a sideways position (haven't these people ever heard of Bluetooth?). You could throw your back out of whack from hauling a foot-high pile of client folders to and from the file cabinet (guess they haven't heard of electronic files, either).
This all sounds pretty innocuous, right? Well, remember that working in the human services field involves some degree of unpredictability. You may often be working with clients who are upset, angry, and convinced you are part of the problem. They may not want to listen to reason that day. Yes, your job is to help them; however, you're also responsible for keeping yourself safe.
You'll need to keep an eye on your surroundings and act proactively to defuse any potentially harmful situations. Some social workers ask a police officer or sheriff's deputy to accompany them to client home visits or meetings in unfamiliar locations. The bottom line: You have resources available to you, but you'll need to ask for them.