Bay Area residents who violate a new ban on burning wood fires on chilly Spare the Air nights could face some of the toughest fines in California — hundreds or even thousands of dollars per violation.Effective today with the start of the burn season, the new Bay Area rule bars people from burning wood fires in fireplaces and wood stoves on bad air nights. The rule also bars excessive smoke from indoors fires any time of year.Offenders — to be identified largely by neighbors phoning in complaints — will get written warnings for the first offense. But subsequent violations can...