Final answer:
Spiral staircases should now be at least 26 inches wide at and below the handrail height for enhanced comfort and safety, based on newer design standards.
Step-by-step explanation:
The width of spiral stairways is an important consideration in building design to ensure safety and functionality. Although there was an older "rule of thumb" that suggested a stairway width of 5 inches side-to-side and 7-8 inches deep, contemporary design standards recommend a more spacious approach. Spiral stairways should now be at least 26 inches wide at and below the handrail height. This adjustment accounts for increased comfort and safety, allowing for easier ascent and descent for individuals of all sizes.
In the construction industry, spiral stairways are designed with specific dimensions to ensure safety and usability. According to newer guidelines, spiral stairways should be at least 8 diameters side-to-side and 15 diameters deep. For example, if the diameter is 24 inches, the width at and below the handrail height should be at least 8 x 24 = 192 inches side-to-side.