Section R. 400.18612 - Doors and doorwaysRule 612.
(1) A doorway that is a part of a means of egress shall be at floor level.(2) A door, including a screen and storm door, that forms a part of an approved means of egress shall open in the direction of egress travel. This rule does not require a door from a resident-occupied room to open into a corridor, except that such a door shall not be hung so as to obstruct egress passage. There shall not be any obstruction at any time to the opening and closing of an egress door or a door from a resident-occupied room into a corridor.
(3) In a building which does not have more than 2 levels, in which both levels exit at grade, and in which elevations between levels are not more than 4 feet, the building will be considered as 1 story and enclosures shall not be required between levels.(4) A revolving door shall not be approved as part of a means of egress. If a revolving door is installed, a side-hinged door that is in compliance with the provisions of this rule shall be installed within 15 feet of each revolving door.
(5) A door that enters a stair shaft or other vertical opening shall not be held in an open position at any time by an under-door wedge or door-holding device.(6) A transom or other similar opening between a room and a corridor or passage is not permitted.Mich. Admin. Code R. 400.18612