Unhealthy air as Camp Fire smoke billows to Bay Area
The air quality in the Bay Area was unhealthy during the week of Nov. 11, 2018 because of the smoke billowing down from the Camp Fire in Butte County. A reading of less than 50 is good, up to 100 is moderate and anything over 100 is unhealthy. A reading of 200 or more is very unhealthy. These numbers refer to a specific amount of pollution in the air, specifically ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide and two sizes of particular matter.