A dogging tool (key) is used on Delaney panic exit devices. When the exit device push bar is pressed in and a dogging key is inserted and turned it will keep the latchbolt retracted. You essentially only have to push or pull the door to open when the exit hardware is "dogged". To release the latchbolt the device must be manually released by re-inserting the dogging key and turning to disengage the mechanical dogging.
Note: mechanical dogging cannot be used on fire exit hardware.
