Which two sources are considered when calculating lighting load for an office building?

Which two sources are considered when calculating lighting load for an office building?

• A. 1.3 VA/SF and the actual connected load
• B. Watt density per square meter and total connected load
• C. Only the actual connected load
• D. Only 1.3 VA/SF

Answer: (A)

Lighting load in an office is determined using two inputs: the general unit load based on area and the actual connected lighting load. For offices, the standard unit load is 1.3 VA per square foot, which represents typical lighting demand per area. In addition, you include the actual connected load of all lighting equipment—the real wattage of fixtures, ballasts, and other lighting components that are installed. By summing the general area-based load with the actual connected load, you get a more accurate total lighting load for sizing feeders and services. Relying on only one source—either just the unit load or just the actual connected load—could under- or overestimate the demand. Also, using metric units (watts per square meter) isn’t the standard approach in this context.

Lighting load in an office is determined using two inputs: the general unit load based on area and the actual connected lighting load. For offices, the standard unit load is 1.3 VA per square foot, which represents typical lighting demand per area. In addition, you include the actual connected load of all lighting equipment—the real wattage of fixtures, ballasts, and other lighting components that are installed. By summing the general area-based load with the actual connected load, you get a more accurate total lighting load for sizing feeders and services. Relying on only one source—either just the unit load or just the actual connected load—could under- or overestimate the demand. Also, using metric units (watts per square meter) isn’t the standard approach in this context.