Nu Calgon 4126-34 Bio-Fresh CD 1 QT Spray Bottle Bio-Fresh cd is a ready-to-use bacteriostat, fungistat and deodorizer based upon chlorine dioxide technology. It is recommended for control of bacteria, mold, mildew, fungi and yeast in IAQ applications. Its EPA registration includes application in HVACR ventilating equipment, including coils, condensate pans, filters and duct-work. Evaporator coils, condensate drain pans, filters and duct-work in air conditioning systems can be an excellent breeding ground for bacteria and mold. Left untreated, it can grow and eventually affect indoor air quality, a major concern of the IAQ movement today. Use of a product like Bio-Fresh cd in a total program such as Nu-Calgon’s IAQ Assurance Program will correct this problem by inhibiting the growth of bacteria or mold.