CDC sets first target for indoor air ventilation to prevent spread of Covid-19

Key Facts

The agency had advised people to ventilate indoor air before, but this is the first time a federal agency has set a target – five air changes per hour – for how much rooms and buildings should be ventilated.
Allen says that although it’s easy to see the guidance only in the context of Covid-19, it will help with many other airborne hazards like wildfire smoke, allergens and other infectious diseases, such as the flu.
Public health officials have long downplayed the role of airborne spread in the transmission of infectious disease, and it took years of lobbying by indoor air quality experts for the CDC to acknowledge the importance of ventilation in controlling the pandemic.
The CDC says better indoor ventilation can reduce the concentration of viral particles in the air, lowering the risk that a person would breathe them in and get sick.