Category: air quality monitoring

CNN article boosts WHO guidelines on average lifetime exposure to particulates

CNN just posted an article supporting the assertion I made in March about needing to wear a mask when the US AQI is above 41. I made this assertion based on the World Health Organization guidelines. The WHO recommends that the average lifetime exposure to particulates should not exceed 10 µg/m3. Neither CNN nor the…



WHO annual mean suggests lower safe air pollution threshold

In a previous article, recommended wearing a mask when the US Air Quality Index is at “Moderate” (AQI 51) or higher. But annual air pollution exposure is usually more salient than short-term exposure unless the air quality on a given day is seriously unhealhty. A recent examination of the World Health Organization’s current guidelines for…



More California wildfires: masks are essential more than ever

The repeated episodes of California wildfires keep getting worse.  For these wildfires, masks are essential, more than ever before.  The Camp Fire in northern California is the worst in the state’s history, and the fires have given many parts of the state the worst air quality in the world. California cities including San Fransisco, Oakland,…