# Double flight Staircase type 4
Staircase direction Left to right Right to left | Waiting step Before going up only Before going up and down
Flight width (a) |  | Riser height (b) |
Thread depth (c) |  | Gap in between (d) |
Number of risers in first flight (e) |  | Number of risers in second flight (f) |
Slab thickness (g) |  | Stringer width (h) |
Stringer depth (i) |  |
Handrail guiding lines offset (k) |  | Handrail guiding lines height (l) |

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