Air Movement, Comfort, and Ventilation in Workstations

Results are presented from a research project to investigate the effects of office partition design on air movement, worker comfort, and ventilation in workstations. The objectives of the study were to evaluate the comfort and ventilation conditions produced by a conventional ceiling supply-and-return air distribution system in workstations separated by (1) solid partitions of different height (75 in. [1.9 m], 65 in. [1.65 m], 42 in. [1.1 m], and 0 in. [partitions removed]) and (2) partitions containing a gap positioned at the bottom of the partition. The project consisted primarily of experiments performed in a full-scale controlled environment chamber (CEC) which a typical modular office environment was set up. The range of partition configurations and environmental parameters investigated included (1) partition height, (2) solid vs. airflow partitions, (3) airflow gap size, (4) supply air volume, (5) supply/room temperature difference, (6) supply diffuser location, (7) heat loud density, (8) workstation size, and (9) cooling vs. heating mode. Under steady-state conditions, multipoint measurements were made of air velocities, air temperatures, and radiant (globe) temperatures to characterize the key environmental variables affecting thermal comfort, and tracer gas methods using multipoint sampling locations were employed to determine the ventilation performance within the test chamber.

The results indicated that variations in solid partition height produce only small differences in overall thermal and ventilation performance. Results also showed that while the existence of an airflow opening at the bottom of office partitions can, in some cases, produce slight increases in air velocities near the floor, there are no significant improvements in comfort conditions or ventilation efficiency within the workstations compared to results obtained for solid partitions. Test parameters that were found to have a more substantial impact on air movement and comfort included heat load density and distribution, supply air temperature, and supply diffuser location.