Which is the required minimum height of risers for a stairway that must have at least one handrail?

The required minimum height of risers for a stairway that must have at least one handrail is 30 inches. When a stairway has a height of 30 inches or more, it is a regulation that a handrail is needed for safety. This requirement is in place to help prevent falls and provide support for individuals as they navigate stairways, especially those that might be more steep or require additional balance support.

Having a handrail assists users, particularly those who may have mobility challenges or are carrying objects, ensuring they have something to hold onto while ascending or descending the stairs. Handrails are a critical component of safety in stair design and are mandated by building codes in many areas.

In terms of stair dimensions, risers that are lower than 30 inches typically do not necessitate a handrail, as they are considered safe enough for most users to traverse without additional support. Thus, the specification for requiring a handrail at this particular height aligns with safety standards intended to minimize risks in built environments.