DISPLACEMENT VENTILATION AS A VIABLE AIR SOLUTION FOR HOSPITAL PATIENT ROOMS

SUMMARY In few environments is the indoor air quality as important as that in hospital patient rooms. The air system must provide protection for the patient, caregiver as well as any visitors that may be in the room. Current codes and standards have been developed with this in mind, often by prescribing an air change rate, thereby ensuring a minimum amount of air movement and purge rate. These have all been put in place on the assumption of a mixing air supply system. Displacement ventilation offers a means of improving the air quality in these spaces, with the indication of lower air change rates. This in turn saves energy and reduces operating costs for the healthcare system. This paper presents the results of a particle study that quantifies the improvement of the air quality in a displacement ventilation system over that of a mixing system in a patient room. The exposure potential of these systems was evaluated along with maximum concentration and decay rate following a sneeze event. The displacement ventilation system showed significant improvement over the mixing ventilation case, even at lower air change rates.