To keep a push bar door unlocked, you use a built-in feature called “dogging” that holds the latch bolt in the retracted position so the door can swing freely without anyone pressing the bar. Most commercial push bars (also called panic bars or exit devices) have a dogging mechanism activated with either a hex key or a keyed cylinder. The method depends on which type of hardware is installed on your door.
What Dogging Does
When you “dog” a push bar, you’re mechanically locking the push pad in its depressed position. This keeps the latch bolt pulled back into the device so it no longer catches the strike plate on the frame. The door effectively becomes a simple push-pull door that anyone can open from either side without activating the crash bar. This is commonly done during business hours when free traffic flow is needed, then reversed at closing time to restore security.
Hex Key Dogging: The Most Common Method
The majority of commercial push bars use hex key dogging. Here’s how it works:
- Locate the hex key slot. Look at the end of the push bar, usually on the bottom edge near one of the mounting points. You’ll see a small hexagonal hole.
- Insert the correct Allen wrench. Common sizes are 3/16″ or 5/32″, but this varies by manufacturer. If you don’t know the size, try a few from a standard set until one fits snugly.
- Press the push pad down and turn the hex key. While holding the bar in the depressed position, rotate the Allen wrench (typically a quarter turn). This engages the dogging mechanism, which pins the latch bolt in its retracted position.
- Release and test. Let go of the push pad. It should stay depressed, and the latch bolt should remain retracted. Push the door open and let it close to confirm it no longer latches.
To re-lock the door later, insert the hex key again and turn it back to the original position. The push pad will spring back out, and the latch bolt will extend to catch the strike plate when the door closes.
Cylinder Dogging: The More Secure Option
Some push bars have a keyed cylinder built into the device instead of a hex key slot. The process is similar: you press the push pad down and turn the key to engage the dogging mechanism. The key difference is security. Only someone with the correct cut key can dog or un-dog the door, whereas any standard Allen wrench of the right size can operate hex key dogging.
Cylinder dogging is the better choice for exterior doors, schools, and any location where you don’t want unauthorized people propping the door open. If your building currently has hex key dogging and you’d like more control, many manufacturers sell conversion kits that let you swap to cylinder dogging on the same exit device without replacing the entire bar.
Electronic Dogging for Scheduled Unlocking
Buildings with access control systems can use electrified exit devices that dog automatically on a schedule. An electric latch retraction (ELR) kit mounts to a standard mechanical push bar and uses a small motor to retract the latch bolt and hold the push pad in the dogged position when energized. When the power signal stops, the bar returns to its normal locked state.
This lets facility managers program exact unlock and lock times through their access control panel, eliminating the need for someone to physically dog every door each morning and un-dog them at night. It also allows remote dogging from a security desk. For double doors, sequencer modules coordinate both leaves so they latch and unlatch in the correct order.
Fire-Rated Doors Cannot Be Dogged
Mechanical dogging is not permitted on fire-rated doors or fire exit hardware. These doors are required to latch positively every time they close so they function as fire barriers. If your push bar is on a fire-rated door, it will not have a dogging mechanism at all, and attempting to modify it to stay unlocked violates fire code. The only way to hold a fire-rated door open legally is with a magnetic hold-open device connected to the fire alarm system, which releases the door automatically when the alarm triggers.
Why Dogging Gets Stuck
If you’ve inserted the hex key and turned it but the push pad won’t stay down, or if the latch bolt springs back out when the door closes, a few things could be going on. Dirt and dried lubricant inside the mechanism are the most common culprits, especially on older devices exposed to weather. A light application of dry lubricant (not WD-40, which attracts grime) into the hex key slot and along the latch bolt can help free things up.
Check the set screws on the dogging assembly as well. These can loosen over time from the vibration of daily use, preventing the mechanism from holding. If tightening them doesn’t solve the problem, the internal dogging assembly may need replacement. This is a relatively straightforward repair for a commercial locksmith and doesn’t require swapping the entire exit device.
Security Risks of Leaving a Push Bar Unlocked
A dogged push bar lets anyone walk through the door from the outside, which is the whole point during business hours but a real vulnerability if forgotten overnight. Hex key dogging is especially risky in settings like schools, where someone could carry a common Allen wrench and dog an exterior door open without authorization, creating an unmonitored entry point.
If your building requires doors to be dogged during operating hours but you’re concerned about unauthorized access, consider these options:
- Upgrade to cylinder dogging so only keyed personnel can change the door’s status.
- Use electronic dogging tied to your access control system, which automatically re-locks doors on schedule and eliminates the possibility of human error.
- Add a door position sensor that alerts security if a dogged door is propped open outside of scheduled hours.
ADA and Opening Force
Dogging a push bar can also help meet accessibility requirements. The ADA standard for accessible doors sets a maximum operating force of 5 pounds for interior doors. A push bar in its normal (un-dogged) state often exceeds this threshold because the user has to overcome the latch bolt’s spring tension. When you dog the device, the latch is already retracted, so the only resistance is the door’s weight, hinges, and closer, making it significantly easier to open. For buildings aiming to improve accessibility at entrances used during business hours, dogging the exit device during operating hours is a practical solution.