Last week on The Building Code Forum, one of the members mentioned that their local police department recommended the installation of overlapping astragals on the exterior pairs at their schools. This left me WORDLESS! It definitely feels like 2 steps forward – 1 step back some days.
This photo, from George Cutler of Quarters Hardware, illustrates the problem (this astragal is installed on the interior, but it would cause the same problem mounted on the exterior). Most exterior pairs on schools will have either rim panic hardware with a removable mullion, or vertical rod panics. Installing an overlapping astragal means that one of the doors will not open without first opening the other door. This is not acceptable for doors in a means of egress…does anyone know where this is stated (this is a quiz)?
In addition, the astragal can actually have a negative effect on security if a coordinator is not installed to ensure that the door leaves close in the correct order. Otherwise, the astragal can prevent one door from closing properly. Here is some more information on astragals on egress doors, and astragals on fire doors.