Proper ventilation and air filtration helps improve indoor air quality by reducing pollutant and moisture levels that can impact health. Indoor air pollution can contribute to a variety of short-term and long-term impacts including irritation of the eyes, nose and throat, decreasing lung function, making asthma worse, and increasing the risk of heart and lung conditions and cancer. Children are at greater risk of adverse effects from poor air quality in general. Indoor exposures have the greatest impact on overall exposure to air pollutants given that most of children’s time is spent indoors. Where possible, removing the source of contaminants is the first and most effective step to improve indoor air quality. The concentration of some air pollutants can be higher indoors than levels found outdoors. Ventilation, in combination with other public health measures, can help reduce the transmission of viruses such as COVID-19.