The Bay Area Air Quality Management District has declared a Spare the Air day Monday due to anticipated unhealthy levels of ozone.

A Spare the Air day means drivers should carpool with friends or co-workers, or telecommute if possible. Drivers are also asked to link
necessary trips and postpone errands.

High levels of ozone can cause throat and lung irritation, or trigger asthma, and can be especially harmful for young children, seniors and
those with respiratory and heart conditions, according to the Air District.

Ozone is formed at ground level when compounds from car exhaust, industrial emissions and household chemicals combine with oxygen on hot and sunny days.

Sunday was also a Spare the Air day.