A complex stairway with curved walls and sections is called what?

• A. Straight Stairway
• B. Flat Curve
• C. Short Radius Spiral
• D. Large Spiral Stairway

Answer: (D)

In escalator and moving walk terminology, stairways are categorized by how they curve and how tight that curve is. A staircase that isn’t straight can be a curved or spiral type, and the radius of that curve matters: a short radius spiral has a tight turn, wrapping quickly around a small circle, while a large spiral stairway wraps around a much bigger circle with a gentler bend. The description “complex stairway with curved walls and sections” fits a large spiral stairway because it implies multiple curved segments built around a sizeable central path, not a tight, compact curve. The other options don’t match the idea of a stairway that includes substantial curvature across multiple sections: a straight stairway has no curve, and a short radius spiral describes a tight-turn design, not a more expansive, complex curved form.