What measures are taken to avoid the supply air becoming contaminated by dirt and particulates collecting in the underfloor plenum and floor diffusers?
The typical velocity of supply air in pressurized plenums is too low for dirt particles to be carried into the air stream and emitted through floor diffusers. Tests have shown that floor diffusers do not blow more dirt into a conditioned space than any other air distribution systems, and in fact, contaminant levels are generally lower in UFAD systems with a floor-to-ceiling air flow pattern. However, further research is still needed to fully understand the health and air quality impacts of UFAD systems. With proper filtration, the amount of dirt or dust entering the underfloor plenum can be minimized. If cleaning is required, the ease with which the underfloor plenum is accessed (compared to extensive distribution ductwork in the ceiling) allows for a regular maintenance schedule to be carried out, avoiding a build up of dirt or dust.
