Smoke and atmospheric particulate created unusually colored skies on Saturday, Nov. 10. Photo: Eric Brandt

If you look out the window and see the sun shining, don’t think that means the air quality has improved. Your eyes are deceiving you. The particle pollution carried to the Bay Area from the Camp Fire in Butte County continues to keep Berkeley’s air in the “unhealthy” category.

The Bay Area Air Quality Management District (BAAQMD) on Monday extended its winter Spare the Air alert through Friday, in the expectation that the poor air quality will persist. It is illegal to burn wood or other solid fuels indoors or outdoors during the alert.

“We need a weather system. We need rain. We need winds. More than anything, we need the fire to get contained,” said Lisa Fasano, communications director, BAAQMD. “We’re really right now at the behest of the fire and the current weather.”

Fasano said people should remain indoors with windows closed. If you have a HEPA filter, that can help, she said. Fasano also noted that libraries have filtered air, so when Berkeley libraries open tomorrow, that could provide some relief.

Fasano said the key problem was for children. Schools are discouraged from holding recess or allowing outdoor sports this week.

For an accurate gauge, check out the air quality index (AQI) map being updated hourly on the Bay Area Air Quality Management District’s website. Berkeley and most of the rest of the Bay Area have been stubbornly stuck in the red zone: an AQI of 151 to 200, which is described as “unhealthy.” For more detail, check the website, run by the federal Environmental Protection Agency. But at the height of concern about air quality last Friday, the AirNow site crashed under the weight of visitors.

Air quality index map from the Bay Area Air Quality Management District on Monday at 11 a.m.

At noon Monday, Berkeley’s AQI was measured at 169. At that level, according to the EPA, “people with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion. Everyone else should reduce prolonged or heavy exertion.”

The main danger comes from particle pollution. AQI measures atmospheric particulate matter (PM) that have a diameter of less than 2.5 micrometers. That’s about 3% the diameter of a human hair. Breathing particle pollution can have adverse health impacts, and, according to the World Health Organization, there is no safe threshold below which no harm would be anticipated. Still, the major effects of particle pollution, according to health experts, is from long-term exposure. (Which is why comparisons to Beijing’s air quality – which is a persistent problem, week after week, month after month – underplays the health consequences of the Chinese capital’s air.)

Air quality in Beijing on Monday.

Masks have limited effectiveness

As Berkeleyside reported last October, when Berkeley’s air quality was similarly bad, ordinary surgeon’s masks or bandanas provide no protection against particle pollution. Masks labelled as N95 or N100 are the minimum requirement for some protection from atmospheric particulate. But Dr. Timur Durrani, associate director of the UCSF Pediatric Environmental Health Speciality Unit, cautioned then that even N95 and N100 masks can provide a false sense of security.

Durrani suggested that there are five criteria to ensure the masks’ effectiveness: the wearer must be 1) medically evaluated and deemed healthy to wear a respirator, 2) fit with the appropriate size respirator, 3) tested to ensure the respirator provides the appropriate seal (which rules out men with beards), 4) trained on wear, fit, maintenance or disposal of the respirator, and 5) able to wear the respirator for the duration of the exposure.

If you choose to wear a mask, the California Department of Public Health provides some clear advice.

Lance Knobel (Berkeleyside co-founder) has been a journalist for nearly 40 years. Much of his career was in business journalism. He was editor-in-chief of both Management Today, the leading business magazine...