scope:

Applications and tasks are limited to:

1. Visual tasks for which the IES has designated Categories P through Y as the Recommended Illuminance Target (Refer to Table 4.1, IES Handbook); and

2. Visual tasks that are Visually Demanding Tasks, as defined in this Technical Memorandum; and

3. Interior lighting applications in which the conditions of performing the task are under a full-fieldof- view, with relatively uniform lighting (luminance ratios do not exceed the Default Luminance Ratio Recommendations (Table12.5, IES Handbook); and

4. Visual tasks for which the task background luminance is 50 cd/m² or greater.

Applications and Tasks Not Included:

The methods described in this TM do not apply to applications and tasks that have been designated as IES Illuminance Categories A through O as the Recommended Illuminance Target, are exterior lighting applications, or are non-visual tasks. Other tasks that are excluded are noted in Section 3.5 under the definition of visually demanding tasks.

The methods described in this TM are based on how light source SPDs affect the ability to discern visual detail. Light spectrum can also impact brightness perception, color rendering, discomfort glare, circadian rhythm and other possible health issues, but these issues are outside the scope of this TM.