The U.S. Department of Energy's CALiPER program has released Report 21.2, which is part of a series of investigations on linear LED lamps. Report 21.2 focuses on the performance of three linear (T8) LED lamps and a benchmark fluorescent lamp in five different troffer types. Also included are the results of a subjective evaluation. The LED lamps were intended as alternatives to T8 fluorescents and were chosen for the study primarily based on their luminous intensity distributions (narrow, medium, and wide beam angles).