Question: how do we filter air?
Answer: Increase Ventilation. Ventilating homes reduces moisture levels, a major problem for indoor air quality. ... 
Beeswax Candles. Beeswax candles act as natural air purifiers. ... 
Salt Lamps. A salt lamp is another great natural air purifier. ... 
Activated Charcoal. ... 
Houseplants. ... 
Essential Oils.