Sales of air and fluid filters in the US will expand 3.8 per cent per annum to $9.7 billion in 2020. Advances will be fueled by a positive economic outlook, including continued strength in manufacturing activity and construction expenditures, as well as by increasing consumer preoccupation with domestic indoor air quality and tap water purity. In addition, continued trends toward the incorporation of smart features and complementary monitoring devices that indicate when a filter must be replaced and toward specialised, industry-specific filtration media will support per unit value gains.