What is the required minimum illumination level in footcandles for artificial lighting in habitable spaces?

The required minimum illumination level for artificial lighting in habitable spaces is set to ensure that these areas are adequately lit for comfort, safety, and functionality. A minimum of 10 footcandles is typically specified for habitable spaces because this level provides sufficient light for general activities such as reading, cooking, and other daily tasks. This standard helps to reduce eye strain and enhances visibility, making it safer and more pleasant for occupants to use these spaces.

Higher levels of illumination might be required in different contexts or for specific activities, while lower levels would not adequately support the needs of the occupants. Therefore, 10 footcandles strikes the right balance to create a livable environment without excessive brightness.