Continued high temperatures and low winds led air quality officials to declare a second straight "Spare the Air" day throughout the Bay Area for Saturday, warning that ozone levels, popularly known as smog, are at unhealthy levels.

The warning from the Bay Area Air Quality Management District asks that area residents refrain from activities that would make the smog worse, such as driving and using other gas-powered engines or painting and engagiong in other fume-producing projects. The district also recommends that persons with respiratory problems restrict strenuous outside activity, particularly in the mid-afternoon.

The District includes Sonoma County south of Healdsburg. Unlike wintertime Spare the Air days, the summer warnings do not include a mandatory ban on wood burning.

This is the third Spare the Air Day of the summer season. For information, visit or call (800) HELP-AIR.

— Sean Scully