The Illuminating Engineering Society (IES) is a North American professional society that develops lighting standards, recommended practices and education. Founded in 1906, it is the main source of the illuminance and uniformity recommendations that designers and codes reference.
For parking, the key IES document is its recommended practice for lighting parking facilities, which sets recommended light levels and uniformity for open lots and structures, including entrances, ramps and stairs. Energy codes, owner standards and security guidelines often build on IES recommendations.
What IES guidance covers for parking
- Light levels. Recommended illuminance for different areas of a facility, by day and night.
- Uniformity. Limits on the ratio between the brightest and darkest areas, which matters more for safety than average brightness.
- Vertical illuminance. Light on faces, which helps people recognize each other and supports security.
- Glare and spill. Guidance to limit glare and light trespass.
- Transitions. Brighter entrances by day so drivers’ eyes adapt.
The Parkonomics view
IES recommendations are where parking lighting design begins. Uniform, well-controlled light does more for safety than simply adding more of it.
Related terms: Illuminance, Luminance, LED Lighting, Glare, Roadway Lighting Committee