Fire interior doors aren't just for commercial interiors where they are required by law, but fire rated interior doors can be put to very good use in the home as well. Fire interior doors generally have ratings of 20, 45 or 60 minute ratings, there are some fire rated doors that are 90 or 180 minute fire rated, but they are generally found in larger commercial applications.
For interior doors that offer fire safe properties, but are not fire rated, consider a solid core interior door. Solid core doors aren't a solid piece of wood, but they have a solid core like mineral fireboard or wood fiber, that offers good sound proofing capabilities and more durability than their hollow counterparts. Since there's more to the door to burn through than the hollow core door, they offer a little more fire protection.
One tip for making the most of safety in fire interior doors, make sure to use certified frames and hardware along with the door for true protection and solid safety, check with the manufacturer of the door for proper hardware and framing systems.