Author: Site Editor Publish Time: 23-12-2025 Origin: Site
Balancing high-level security with emergency safety is one of the toughest challenges for building managers and architects. You need to keep unauthorized visitors out while ensuring that everyone inside can leave quickly in an emergency. This is where the panic exit device—often called a door push bar—comes into play.
While you might see these bars on almost every commercial door, not all of them work the same way. The mechanism hidden inside the door makes a massive difference in durability and protection. Specifically, the mortise-style exit device stands out as a robust solution for buildings that cannot compromise on security.
If you are upgrading your building's hardware or specifying products for a new project, you likely have questions about which device is right for you. We have compiled the most common questions about mortise-style door push bars to help you understand why they are the preferred choice for high-traffic and high-security areas.
A door push bar, also known as a panic bar or crash bar, is a horizontal metal bar fixed to the inside of an outward-opening door. Its primary function is life safety. When the bar is depressed—usually by someone pushing against it or a crowd pressing forward—it retracts the latch mechanism, allowing the door to open freely without requiring a key or rotary motion (like turning a knob).
These devices are mandatory in many jurisdictions for buildings with high occupancy loads, such as schools, hospitals, theaters, and shopping centers. The genius of the design is its simplicity; in a panic situation where visibility is low or adrenaline is high, users don't need to think about how to operate the door. They simply push and exit.
This is the most critical technical distinction to understand. While the bar on the outside might look similar, the locking mechanism differs significantly.
Rim Exit Devices are surface-mounted. The latch bolt projects from the device housing and engages a strike plate mounted on the surface of the door frame. They are easier to install but offer slightly less security against forced entry because the latch is exposed.
Mortise Exit Devices, on the other hand, integrate with a mortise lock body that is installed inside a pocket (mortise) cut into the edge of the door. The push bar operates this internal lock body. Because the latch bolt is housed within the door structure itself, it offers superior strength and resistance to tampering.
To help you decide which is better for your application, here is a quick comparison of the two main styles.
Feature | Rim Exit Device | Mortise Exit Device |
|---|---|---|
Installation | Surface mounted (easier retrofit) | Installed inside door edge (requires prep) |
Security Level | Moderate | High (integrated into door structure) |
Durability | Good for standard traffic | Excellent for high-abuse/high-traffic areas |
Aesthetics | Visible hardware on door surface | Cleaner look, hardware hidden in door |
Door Thickness | Flexible | Requires specific door thickness (usually 1.75"+) |
The decision to use a mortise-style door push bar usually comes down to three factors: security, durability, and aesthetics.
Because the locking mechanism is embedded inside the door, it is much harder for intruders to tamper with or jimmy the latch. Many mortise locks, like those offered by Keyman Lock, feature a deadlatch mechanism and are constructed to meet rigorous standards like ANSI/BHMA Grade 1. This makes them ideal for exterior doors where security is a priority.
Mortise locks are notoriously durable. The internal placement protects the critical components from direct impact and environmental wear. For busy entrances in schools or hospitals, a mortise device typically offers a longer service life than surface-mounted alternatives.
Mortise exit devices function seamlessly with various outside trims (levers or pulls). Since the lock body is standard, you can often match the lever design with other doors in the building that use standard mortise locks, maintaining a consistent visual style throughout the facility.
Yes, many are, but you must check the specific certifications. A standard "panic device" typically features a "dogging" mechanism that allows you to hold the latch retracted (keeping the door unlocked) during business hours. However, holding a fire door open defeats its purpose.
Therefore, fire-rated exit devices generally do not have a mechanical dogging feature (unless connected to a fire alarm system that releases the latch).
When selecting a product, look for specific ratings. For example, Keyman Lock products, such as the X8 and X9 series, adhere to strict standards:
UL 10C & ULC-S104: Fire Rated up to 3 Hours.
ANSI/BHMA A156.3 Grade 1: The highest grade for durability and security.
Ensuring your hardware carries these labels is essential for passing building inspections and ensuring occupant safety.
Not exactly. Because the lock body sits inside the door, the door must be prepared (mortised) to receive it.
Door Material: Hollow metal and wood doors are most common. Glass or narrow-stile aluminum doors often require specific "narrow stile" devices.
Door Thickness: The standard thickness is usually 1-3/4 inches (45mm). Thinner doors may not have enough depth to house the lock body.
Handing: Unlike some universal rim devices, mortise locks are often "handed" (Left Hand vs. Right Hand), although many modern high-quality locks are field reversible.
If you are retrofitting an existing door, you must ensure the existing cutout matches the new lock body dimensions. If the door was previously set up for a rim device, switching to a mortise device will require significant carpentry or metalwork.
Despite their durability, no mechanical device is maintenance-free. To ensure your door push bar functions correctly during an emergency:
Visual Inspection: Check for loose screws, missing end caps, or obstructions blocking the bar's movement.
Function Test: Push the bar to ensure the latch retracts fully and smoothly. The door should open without excessive force (typically less than 15 lbs of pressure).
Lubrication: Periodically lubricate the internal components of the mortise lock body according to the manufacturer's instructions. Avoid heavy greases that attract dust; dry graphite or silicone sprays are often preferred.
Strike Alignment: Ensure the latch bolt engages the strike plate securely. Door sagging over time can cause misalignment, preventing the door from locking or opening properly.
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Choosing the right hardware is about more than just meeting code; it is about ensuring peace of mind. A mortise-style door push bar offers a superior blend of heavy-duty security and reliable safety that standard devices often cannot match. Whether you are outfitting a school, a hospital, or a commercial office, investing in high-quality, certified hardware ensures your building remains safe for years to come.
If you are looking for ANSI Grade 1 hardware that stands up to the toughest conditions, Keyman Lock offers a range of fire-rated exit devices and mortise locks designed for professional applications.
