Public: Fire
Two-way Nested Fire Door   (+4, -1)  [vote for, against]
An opposite fire door set in a fire door.

Fire doors have a push bar on one side and a handle on the other.

The push bar is much more convenient and sanitary, but on the other side pushing would do no good because the door frame is in the way. Having a two-way door of the restaurant variety would probably violate fire code regulations. Therefore, take a perfectly good fire door and cut a rectangular hole in it. Then buy a slightly smaller fire door and mount it in the hole, pushbar on the larger door's handle side. That way the sub-door or main door can be chosen according to handle preference.

Part of the rationale for the one-way fire doors is to direct evacuation. Assuming perfectly rational escapees with perfect information, there could be more optimal routes for escape given certain places on fire and starting locations.
-- Ketchupybread, Oct 31 2010

[mouseposture, Oct 31 2010]

By the logical fallacy that devices meeting regulations are superposable to produce new devices meeting the same regulations.
-- Ketchupybread, Oct 31 2010

Wouldn’t the smaller door hit the push-bar?
-- pocmloc, Oct 31 2010

I imagine it is possible to make a 2 way door that complies with regulations but this isn't how one should go about it.
-- Spacecoyote, Oct 31 2010

The National Fire Prevention Association (who claim to be an authority on the subject) say "the door cannot be modified in the field except for the items noted in NFPA 80" a copy of which is available for a mere $40.50.

As to what modifications may be made at the factory, perhaps the problem there is loss of certification. You could no longer claim the door passed pressure- and temperature- tests specified in the code, without going to the expense of repeating those tests.

[+] for "superposable"
-- mouseposture, Oct 31 2010

I didn't say it would be easy.
-- Spacecoyote, Oct 31 2010

// Assuming perfectly rational escapees with perfect information //

One should never assume that.
-- BunsenHoneydew, Feb 02 2020

Why not ?
-- 8th of 7, Feb 02 2020

random, halfbakery