Indoor air quality (IAQ) is referred to as: "the quality of the air in a home, school, office, or other building environment" . According to the United States Environmental Protection Agency, IAQ potential impact on human health can be significant. Indeed, long-term exposure to air pollution [mostly given by nitrogen oxides (NOx), and volatile organic compounds (VOCs)] has serious health effects. It has been shown that this can eventually lead to premature mortality . Variegated are the sources of indoor pollution: combustion, cleaning supplies, and the building materials themselves . Lockdowns/restrictions imposed by Governments during the (ongoing, at the time of writing) COVID-19 pandemic on the one hand resulted in less industrial, and in general, outdoor emissions. However, this situation led to an (unrequested) increase of the time we stay home, thus to a non-negligible worsening of the IAQ. This in turn led to negative health outcome on human-beings during the COVID-19 lockdowns .