Center for the Built Environment

The tests described in the subject report were performed at UC Berkeley by Research Specialist Fred Bauman, P.E., a very experienced researcher and writer in the field of air distribution (see References). The purpose of the tests was to measure and confirm the ability of APACS to provide the needed cooling to satisfy each and every individual occupant for total comfort control under all foreseeable conditions.

The test facility measured only dry (sensible) heat. As the report indicates, the cooling effect of skin moisture (latent cooling) is equal to or greater than sensible cooling.  Especially at extremes when the occupant is very hot and perspiring, he can increase APACS air flow to remove all the heat generated, provide thermal equilibrium, and thus make himself comfortable.

The heat generated (metabolism) can vary from 360 to 3000 Btuh per person, a range of almost 10 to 12. This is the reason for providing up to 70 CFM of personal air flow – even though this high heat output is rare in an office environment. The norm is 360 to 800 Btuh, which requires only 0 to 30 CFM, and maximum air velocity of 200 FPM (1 m/s), or 2.3 MPH, which is very comfortable (see Table 3, Pg. 11).

This study demonstrates the ability of APACS to remove variable amounts of heat with localized air flow instead of air temperature change, and to provide perceived temperatures for the individual through a range of 0° to 15°F (65° - 80°F) without affecting other people.