Chino IAQ work centers on agricultural-history fine particulate management, longer cooling-season filter cycling, and wildfire smoke recovery. South and west Chino still have working dairy preserve land and farm fields — outdoor air carries heavier fine particulate and ag-related allergens than central IE cities. Standard 1-inch MERV 8 filters load up in 20-30 days during pollen and dust events. 4-inch MERV 13 media filter cabinets with 6-month change cycles outperform monthly 1-inch swaps. Lower-elevation longer cooling season means HVAC systems run more cumulative cycles per year, processing more outdoor air through filters — filter quality matters more in Chino than upper-IE cities.