This report presents results from a study whose primary goal was to investigate the effects of noise from building mechanical systems on human task performance and perception and relate the results to existing indoor noise criteria ratings. Two phases were conducted

The goal of Phase I was to examine how the time length of exposure to noise and the types of tasks studied impact performance and perception testing. The results were then used to inform the testing procedures for Phase II. Phase II was the main study, which investigated the effects of two different sets of noise signals from building mechanical systems on human task performance and perception.