Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 25·3.10
Change of direction for long consecutive flights
Stairs with more than 36 consecutive rises must include at least one change in direction of at least 30° between flights to break up the length.
A stair of more than 36 rises in consecutive flights should have at least one change in direction between flights of at least 30° (see Diagram 3.3).
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/regional/Technical Booklet H - Stairs Ramps Guarding and Protection from Impact.pdf