Rim exit devices, otherwise known as panic bars, or crash bars are essential for fire code compliance. They also make it easier for the handicapped to exit. When installed correctly a rim exit device allow someone to make one motion to exit. You have to remember where there’s fire there’s smoke and that blinds you.
Panic bars come in a couple different styles.
Trapeze panic bars
Vertical rod exit devices. These bars are great for door without a center mullion, where a latching rim exit device wont work.
These are rim exit panic devices.
Lastly there are concealed vertical rod exit devices.
Exit devices come with a number of different exterior trims. Each of these outside trims are slightly different for every manufacturer. The bars will either come with some kind of a pull handle on the outside requiring a key. For a lever handle that will require a key to lock and unlock the panic bar for the day. They can also come with no outside lock of any kind. Install this if you don’t want to have any access from the outside whatsoever.
Sometimes these bars are also referred to as crash bars or push bars too so when you try to replace one you’ll find them sold under many name.