It's a Dog-Eat-Dog World Out There...

by T.J. Gottwalt, CSI, CDT, AHC, Essex Industries

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intumescent seals are now required on some doors

 

What in the world is “dogging”, anyway? I’ve heard this question many times in the course of my career, so it must be confusing enough to warrant an article explaining it. The word “dog” has many definitions, but in the context of door hardware, dogging is nothing more than the “holding in a retracted position” of a latchbolt, usually on an exit device.

When an exit door needs to be unlocked, more often than not this is accomplished by dogging the exit device push rail down. This holds the latchbolt retracted so that the door may operate in a push/pull fashion. This is good for a number of reasons. Primarily, it eliminates the cycling of the latching mechanism every time the door is opened, thus saving a considerable amount of wear and tear on an exit device. There are no moving parts when a device is manually dogged. Secondly, it simply makes it easier to open the door. From outside the opening, one only needs to pull the door open. No twisting or grasping of levers or knobs is required, making the opening much more accessible. Finally, by not requiring the latch to be retracted each time the door is cycled, one can eliminate operating trim such as levers from the exterior of a building, where they are subject to great abuse. By allowing the dogging of an exit device, pulls can be used instead of levers. This can make an opening more aesthetically pleasing as well, by allowing the selection of designer type pulls.

A common option applied to exit devices, especially in public and institutional applications, is “cylinder dogging”. Cylinder dogging is used to stop unauthorized dogging of an exit device. Normally, the dogging of an exit device is accomplished with the use of a hex key or allen wrench. These items are commonly available, and the opportunity exists for someone unauthorized to be dogging or undogging exit devices. To eliminate this, cylinder dogging requires the use of a key to dog or undog an exit device. This is an excellent option to apply in school work.

As I wrote this article, I was wondering just where the term “dogging” actually came from. I mean, why not just call it “holding” or “retracting” or something a little more understandable. As it happens, the dictionary sheds some light on this. Under “dog” in the dictionary, I found the following reference: “any of various, usually simple, mechanical devices for holding, gripping, or fastening that consist of a spike, bar, or hook.” Inside an exit device, there is actually just such a device to hold the push rail (and thereby the latchbolt) in a retracted position. Most manufacturers utilize some type of a hook, attached to a cam.

So that’s why it is referred to as dogging. Just don’t be caught wearing milkbone underwear.

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