I’ve received a few questions recently about 3-hour pairs and how to handle the hardware:

I have a 3-hour pair of hollow metal doors that requires an overlapping astragal in order to comply with the manufacturer’s listings.  Both leafs have vertical rod fire exit hardware.  How do I avoid an egress conflict?

While some hollow metal door manufacturers’ listings may allow 3-hour-rated fire doors with vertical rod fire exit hardware on both leafs, it’s important to know whether the listings require an overlapping astragal for 3-hour doors, rather than a split astragal.  If an overlapping astragal is required, this effectively prohibits the use of two vertical rod exit devices on these pairs.

According to NFPA 80:  Doors swinging in pairs, where located within a means of egress, shall not be equipped with astragals that inhibit the free use of either leaf.

This is a key requirement for egress doors – when a door is provided for egress purposes, it has to allow egress as required by code.  Although there are specific types of electrified hardware systems that are allowed by the codes to deter or delay egress if certain criteria are met, the intent of the model codes is that each leaf of a pair with panic hardware or fire exit hardware would allow egress.  If an overlapping astragal is installed on one leaf of a pair with vertical rod devices on both leaves, the door that is being overlapped by the astragal can not be used unless the other leaf is opened first.

So how is this problem resolved?  If the manufacturer’s listings require an overlapping astragal and both leaves require panic hardware, I would specify vertical rod fire exit hardware (CVR or LBR) on one leaf.  The other leaf would have mortise fire exit hardware and the astragal would be attached to the outside of this leaf.  The opening would also require a coordinator and a carry bar.  The door with the mortise device functions normally for egress.  The door with the vertical rod device can also be opened for egress, and the carry bar will push the other leaf open far enough for the vertical rod leaf to clear the astragal and continue opening.  The coordinator will ensure that the doors close in the proper sequence so they can latch.  In some cases, automatic flush bolts may be allowed on one leaf instead of vertical rod fire exit hardware.  In that case the coordinator would still be required but the carry bar would not.

I hope that all makes sense!  🙂

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