1. There shall be at least one accessible interior route through the hallway(s), consistent with the requirements of CBSC, Chapter 11A, from the accessible primary entrance of the dwelling unit to a powder room or bathroom, common use room, and the kitchen;

2. Accessible interior routes shall have a minimum width of forty-two inches; except that a thirty-nine-inch hallway width is permitted when all doors leading to any bathroom or powder room, if on the primary entry level, have an accessible minimum clear door opening of thirty-four inches, and a thirty-six-inch hallway is permitted when all doors leading to any bathroom or powder room on the primary entry level have a minimum clear door opening of thirty-six inches;

3. On accessible interior routes, no sunken or raised areas are permitted between the primary entry and bathroom or powder room, the accessible common use room, the accessible bedroom and the accessible kitchen; and

4. Handrail reinforcement must be installed on one or both sides of accessible interior routes.