Where seating rows have 14 or fewer seats, the minimum clear aisle accessway width shall be not less than 12 inches (305 mm) measured as the clear horizontal distance from the back of the row ahead and the nearest projection of the row behind. Where chairs have automatic or self-rising seats, the measurement shall be made with seats in the raised position. Where any chair in the row does not have an automatic or self-rising seat, the measurements shall be made with the seat in the down position. For seats with folding tablet arms, row spacing shall be determined with the tablet arm in the used position.
Exception: For seats with folding tablet arms, row spacing is permitted to be determined with the tablet arm in the stored position where the tablet arm when raised manually to vertical position in one motion automatically returns to the stored position by force of gravity.
For rows of seating served by aisles or doorways at both ends, there shall be not more than 100 seats per row. The minimum clear width of 12 inches (305 mm) between rows shall be increased by 0.3 inch (7.6 mm) for every additional seat beyond 14 seats where seats have backrests or beyond 21 where seats are without backrests. The minimum clear width is not required to exceed 22 inches (559 mm).
Exception: For smoke-protected assembly seating, the row length limits for a 12-inch-wide (305 mm) aisle accessway, beyond which the aisle accessway minimum clear width shall be increased, are in Table 1029.12.2.1.
[BE] TABLE 1029.12.2.1
SMOKE-PROTECTED ASSEMBLY AISLE ACCESSWAYS
| TOTAL NUMBER OF SEATS IN THE SMOKE-PROTECTED ASSEMBLY SEATING | MAXIMUM NUMBER OF SEATS PER ROW PERMITTED TO HAVE A MINIMUM 12-INCH CLEAR WIDTH AISLE ACCESSWAY | |||
| Aisle or doorway at both ends of row | Aisle or doorway at one end of row only | |||
| Seats with backrests | Seats without backrests | Seats with backrests | Seats without backrests | |
| Less than 4,000 | 14 | 21 | 7 | 10 |
| 4,000 | 15 | 22 | 7 | 10 |
| 7,000 | 16 | 23 | 8 | 11 |
| 10,000 | 17 | 24 | 8 | 11 |
| 13,000 | 18 | 25 | 9 | 12 |
| 16,000 | 19 | 26 | 9 | 12 |
| 19,000 | 20 | 27 | 10 | 13 |
| 22,000 and greater | 21 | 28 | 11 | 14 |
For SI: 1 inch = 25.4 mm.
For rows of seating served by an aisle or doorway at only one end of the row, the minimum clear width of 12 inches (305 mm) between rows shall be increased by 0.6 inch (15.2 mm) for every additional seat beyond seven seats where seats have backrests or beyond 10 where seats are without backrests. The minimum clear width is not required to exceed 22 inches (559 mm).
Exception: For smoke-protected assembly seating, the row length limits for a 12-inch-wide (305 mm) aisle accessway, beyond which the aisle accessway minimum clear width shall be increased, are in Table 1029.12.2.1.