A 30 ft by 40 ft classroom with 8 ft high ceilings will have an ambient lighting target illuminance of 70 fc at a work plane that is 28 inches above the floor. It is anticipated that the ceiling reflectance is 0.50 and the average wall reflectance is about 0.3. The space will be illuminated with surfacemounted, prismatic wraparound luminaires with four lamps, as shown in Figure 20.16. The initial output of the fluorescent lamps is 2,850 lumen. The light loss factor will be assumed to be 0.70. Neglecting the spacing criteria, determine the minimum number of luminaires required to provide uniform illumination in the space. (Type in the number only)

A 30 ft by 40 ft classroom with 8 ft high ceilings will have an ambient lighting target illuminance of 70 fc at a work plane that is 28 inches above the floor. It is anticipated that the ceiling reflectance is 0.50 and the average wall reflectance is about 0.3. The space will be illuminated with surfacemounted, prismatic wraparound luminaires with four lamps, as shown in Figure 20.16. The initial output of the fluorescent lamps is 2,850 lumen. The light loss factor will be assumed to be 0.70. Neglecting the spacing criteria, determine the minimum number of luminaires required to provide uniform illumination in the space. (Type in the number only)

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter17: Commercial And Industrial Air-conditioning Control Systems

Section: Chapter Questions

Problem 24RQ

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