SAN FRANCISCO — Mistakes were made in alerting the public about potentially dangerous pollution created by a huge fire at a Chevron Corp. refinery last month, regulators said Monday.

The disclosure came as the Bay Area Air Quality Management District held a public meeting in San Francisco to discuss its response and the myriad investigations into the Aug. 6 fire that started after a leak in an old pipe at the Richmond facility.

Regulators also told those who attended that they are working to improve pollution monitoring during emergencies. District executive officer Jack Broadbent said the initial, incorrect assertion that all air quality samples taken near the refinery fire were safe "clearly fell short."

"The public was suffering from this event," he said.

More than 15,000 people sought medical attention for breathing complaints and eye irritation, though officials said only three required hospitalization.

The company has not set a timetable for when the crude unit that was destroyed by the fire will restart operations. The site is currently the focus of investigations by state and federal agencies, so access is strictly controlled.

Gasoline prices in California rose sharply in the days after the unit was taken offline. Some analysts said the increase was due in part to the supply disruption caused at the state's third largest refinery.

The average price for a gallon of regular gasoline in California on Aug. 7 was $3.86. On Monday, it was $4.15.

The district is looking at deploying more air monitors near the refinery, and studying new, mobile air-monitoring stations that can be set up quickly during an emergency.

Nigel Hearne, general manager of the refinery, said the refinery as a whole is still producing fuels, though at a reduced rate because of the loss of the crude unit destroyed by the fire.

"Safety is our first business, and any comment to the contrary is incorrect," Hearne said.

Chevron had been working with the city of Richmond prior to the fire to build three, community air monitoring stations that will improve the ability of residents to know when air quality becomes dangerous, Hearne said.

Once the new stations are up and running, Hearne said, a website will allow residents to find real-time pollution data.

The refinery fire has also prompted Contra Costa County to look for a new contractor to run its emergency warning phone system.

It took more than three hours for the phone system to call 18,000 people on the night of the fire, said Randy Sawyer, the county's chief environmental health and hazardous materials officer.

"That should be shorter," he said.