R303.7

Section R303.7 is titled 'Interior stairway illumination' and covers the requirements for providing light on stairways inside a dwelling. Requirement for artificial light, elements of the stairway that must be illuminated, the minimum brightness, the location where the brightness must be achieved, and switches at each level where the stairway has 6 or more risers is established. The purpose of this section is to prevent trip and fall hazards. This section has an exception that eliminates the need for switches where other specific lighting controls are provided. The purpose of this exception is to allow for practical alternatives to manual circuit controls.

The model shows a stairway with 6 risers that has 3-way switches at the top and bottom, which are being used to turn the light on and off from both locations.