If you are looking to light a parking lot or a roadway, a maintained average of .7 to 3.2 foot-candles is the appropriate amount of light that should be generated by the type of fixture you are using. This is important to note because if parking lot or roadway lights are too bright, drivers will be unable to discern objects beyond the light levels on the street. Overlit roads are potentially dangerous when there are pedestrians, bikers or animals near the road or trying to cross the street. Similarly, light levels that are too low will not provide the sufficient necessary needed for high-traffic, pedestrian-heavy areas. Therefore lights located in remote locations are on the lower side of the foot-candle spectrum, whereas urban areas filled with pedestrians often have a higher foot-candle average.
Non-profit organizations like the International Dark Sky Association are leading efforts to reduce light pollution. They have approved certain fixtures that fit their guidelines as lights that qualify as “dark sky friendly.” (Ember LED’s products are identified as IDA approved fixtures.) Check out their guidelines for good exterior lighting plans to learn about the importance of designing specific placement, time, intensity and color of outdoor lights.
When lighting a site designated as construction work zones or recreational sites, 5 foot-candles is generally the minimum. This measurement is the minimum amount to provide the appropriate amount of light to ensure safe and effective construction work, reinforce traffic control plans and protect the safety of the public. Nighttime construction work can oftentimes be dangerous and and require large machinery. Because of this, bigger jobs such as pavement patching, installations or structural fills may require up to 20 foot-candles. Similarly, while your local soccer field may use 20 foot-candles for nighttime play, professional stadiums are lit up to 75 or more footcandles! This type of lighting provides enough light generated during the daytime and are used specifically for large crowds and televised events. Take a look at the nighttime lighting guidelines for work zones provided by WorkZoneSafety.org for construction zone information and lighting standards for the US soccer foundation for details on soccer stadium lighting.
Ultimately, each space requires different lighting levels. But regardless of whatever location you are looking to light, it is vital for every application to maintain uniformity, control glare and reflections, provide contrast for shadows and allow lighting to reveal sufficient detail.