Von Duprin 98/99: Exit Device for a Hollow-Metal Fire Door
Posted by Kent on 3rd Aug 2026
If the door is hollow metal and it might carry a fire label, the storefront device is the wrong tool. This is where the Von Duprin 98/99 earns its reputation. It's the heavyweight rim exit device, the one you put on a steel door in a school, a warehouse, a stairwell, and it takes a beating that would fold a lesser bar. Let me walk you through speccing it so the box that arrives is the one the opening needs.
98 or 99, the finish difference nobody explains right
People assume 98 and 99 are different mechanisms. They aren't. Same device, same guts. The 99 has a smooth mechanism case; the 98 has a grooved case. That's the whole difference. Pick on looks, match what's already on the other doors, and move on. If the building runs one, order the same for a matched set. I lean 99 out of habit; the smooth case wipes down cleaner in a food or medical setting.
Fire-rated or not, settle this before anything else
The plain 99 you see first is the non-fire-rated version. Most hollow-metal doors that get a panic bar are on a rated wall, a stairwell, a corridor cross-door, a mechanical room. Those need the fire-rated device, ordered with the -F designation. The fire version has no mechanical dogging (you can't hold the latch retracted), because a fire door has to positively latch every time it closes. Order a non-rated device for a labeled opening and you've bought a code violation. Check the frame for the metal fire label first. If it's there, you need -F.
EO or night latch, how people get back in
The 99EO is exit only. Push to get out, nothing on the outside. Perfect for a back exit, a stair discharge, an emergency-only door. When you need people to come back in with a key, a receiving door, a side entrance for staff, you want the 99NL, night latch, which adds an outside pull with a keyed cylinder. Decide who needs to enter before you buy. Adding outside trim to an EO later means the 990 trim, a cylinder, and matching prep, more than just bolting on a handle.
Sizing the bar and the finish
The 3 in 99EO-US26D-3 is the device size for a standard door up to 3 feet wide; the 4 covers up to 4 feet. Size to the actual leaf. A bar sized short leaves dead space where the push doesn't work; sized long, it overhangs the edge.
US26D satin chrome is the commercial default and the one I'd stock. It hides scuffs and matches most other hardware on a steel door. Get the size and the finish right and this device disappears into twenty years of service.
Common questions
What's the real difference between 98 and 99?
Just the case finish. The 99 is smooth, the 98 is grooved. Same mechanism inside. Match whatever the building already runs.
How do I know if I need the fire-rated version?
Look for a metal fire label on the door or frame. If it's there, order the -F device. Fire-rated devices can't be dogged (held open); they must latch every time.
Can I get keyed entry from outside?
Yes, order the 99NL night latch, which adds an outside keyed pull. The 99EO is exit only with nothing on the outside.
What size do I order?
Match the door width: the 3 covers a standard 3-foot leaf, the 4 covers up to 4 feet. Measure the door.
Lock Depot stocks the Von Duprin 98 and 99 in EO and night-latch, fire-rated and standard, sized to your door. Start at the Von Duprin hub, or if your door is aluminum storefront instead of hollow metal, read Von Duprin 33A: Exit Device for an Aluminum Storefront Door. Or call 877-365-5625 and tell us three things: fire label or not, EO or keyed entry, door width. Three answers and we read you the model.