Profiles of Innovative State Programs: California – Ventilation and Filtration Guidance

The California Department of Public Health (CDPH) Air Quality Section conducts multidisciplinary research to support IAQ technical and policy solutions and provides technical guidance on a variety of IAQ topics.

Why is this Project Important? 

Outside air ventilation and air filtration are key strategies for improving indoor air quality. During the COVID-19 emergency, ventilation and filtration became widely recognized as critical strategies for reducing exposure to infectious aerosols. At the same time, it became clear that many buildings were not equipped to provide adequate ventilation and filtration for controlling infectious disease transmission and for reducing indoor levels of other common pollutants. 

What Materials Were Developed?

CDPH published detailed technical guidance on ventilation and filtration designed to supplement COVID-19 rules issued by the California’s occupational safety and health agency. The CPDH guidance recommends “practical steps that building operators can take to promote better ventilation, filtration, and air quality in indoor environments for the purpose of reducing the spread of COVID-19 and other aerosolized infectious agents.” The guidance (which is not intended for use by healthcare facilities) includes general considerations as well as specific measures for improving natural ventilation, determining and improving mechanical ventilation function, using portable air cleaners, and providing ventilation during wildfire smoke episodes. It also includes a list of external resources.

How Can You Learn More?

View the CDPH Guidance: Interim Guidance for Ventilation, Filtration, and Air Quality in Indoor Environments

View CDPH information on other IAQ topics: CDPH Air Quality Section