The Plasmacluster 7000 Series FPK50UW Air Purifier by SHARP is your choice for medium-sized rooms. Effective up to 1,253 sq. ft. at one air change per hour, the FPK50UW will filter the air in the AHAM Suggested Room Size of 259 sq. ft. at 4.8 air changes per hour. Shop Sharp Air Purifiers!