In the meantime, displacement ventilation is being used in facilities that do not deal with acute-care needs. (It is worth noting that Dell Children's hospital utilizes underfloor air distribution in its nonclinical, administrative areas.) The new Dan Abraham Healthy Living Center at the Mayo Clinic in Rochester, Minnesota, was designed by BWBR Architects and PSA-Dewberry around an approach to wellness that emphasizes research and the application of advanced technology.

Inside the 115,000-square-foot building-which includes spaces for aerobic conditioning, strength training, and massage therapy-a 7,500-square-foot pool enclosure, containing three pools for swimming and aquatic therapy, received special treatment by HVAC designers.

 

The pool enclosure at the Dan Abraham Healthy Living Center features underfloor air distribution. Photo © Don Wong Photo, Inc.; drawing courtesy LKPB Engineers

 

 

Two large air-handling units serve the main program spaces of the building, while a third, separate unit was designed strictly for the pool enclosure. This unit keeps the pool area under negative pressure so that air is drawn into it, preventing chlorine odors from escaping into adjacent spaces. "In considering patron comfort and health, the ultimate goal was to eliminate chlorine odors in this area," explains Mike Morris, of LKPB Engineers.

Conditioned air is delivered around the perimeter of the pool via an underground concrete air plenum. This allows the conditioned air to evenly and slowly rise into the pool enclosure, minimizing the chill to a wet swimmer walking around the pool. The even distribution also helps prevent chloramines from collecting on the pool deck. A UV-light treatment system is located in the pool recirculation piping to break down the chemical properties of chloramines, helping to eliminate the amount of chloramines in the water, and ultimately, in the air.

The design of health care facilities has traditionally focused on patient health and safety. Recent projects are proving that there is no better way to do this than by designing healthy buildings. "Health care projects currently represent a very small percentage of total LEED projects," cites Adele Houghton, AIA. But Houghton, the  Green Guide for Health Care project manager, also points out that that number has grown significantly since the launch of the guide's Version 2.0 in November 2004. And the number is expected to continue to climb as the country experiences the largest health care construction boom in more than half a century.