Illuminating Engineering Society of North America (IESNA) Guidelines

This guide explains how to provide room ambient light levels consistent with the guidelines of the Illuminating Engineering Society of North America (IESNA), a recognized technical authority of quality practices in the lighting industry. These are light levels that will cover all but highly specialized uses of a space.

The IESNA Guidelines are expressed in foot candles (FC) of illumination, a common measurement in the lighting industry. See the examples below for common lighting experiences expressed in foot candles:

• Bright moonlit night: 1/100 FC
• Enough light to see in a dim room: 1 FC
• Ample light to move about in a room: 3 FC
• Kitchen counter with undercabinet lights: 20 to 90 FC

This guide covers ambient lighting requirements, i.e. the light required for general circulation and occupancy of a room. For kitchens and bathrooms, because cabinetry, appliances, and fixtures are normally a part of initial construction, this guide includes task lighting recommendations for the primary task areas of the room.

The table below presents the IESNA Guidelines that apply to residential construction:

Table 1: IESNA Lighting Design Guidelines for Residences