What is Foot-candle (fc)?
A foot-candle (fc) is a unit of measurement that expresses the intensity of light cast on a surface. It is defined as the illuminance on a one-square-foot surface from a uniform source of light one foot away. This metric is commonly used in lighting design and electrical planning to ensure appropriate brightness levels for specific tasks or environments.
Electricians use foot-candle measurements to design and evaluate lighting layouts in residential and commercial electrical systems. For instance, an office space may require 30–50 foot-candles for adequate visibility and comfort, whereas warehouses may need different levels depending on activity zones. Understanding and applying the correct foot-candle level helps enhance energy efficiency, visual comfort, and safety.
Proper lighting, measured in foot–candles, ensures that electrical installations meet code requirements and user needs. It’s particularly crucial in spaces like workshops, kitchens, or retail areas, where task lighting significantly affects productivity and safety.
