Orange County's Emergency Operations Center, its nerve center during such disasters as October's wildfires, needs renovation or it may find itself a victim of a disaster, according to a grand jury report released Tuesday.

Backup power is inadequate, the sewer system can be overloaded, and smoke wafted in during the fires, prompting people to wear breathing masks, the report said.

The grand jury recommended that the county sheriff install an air filtration system before the 2009 fire season and seek additional funding from the Board of Supervisors for sewer improvements.

Assistant Sheriff J.B. Davis, who is in charge of the facility, said the department was reviewing the report.

"Public safety and the health of our employees and staff who man the Emergency Operations Center is our highest priority," Davis said in a prepared statement. "We are confident that neither public safety nor the health of our staff is in jeopardy at this time."

Davis said the department would reply to the findings. , -- as is required by law.

-- and that the response would be made public after a review by the presiding judge.

According to the report, the facility is deficient "in infrastructure, including the access road, sanitary sewer system and fire protection system," and its heating, ventilation and air conditioning are also deficient.

A sheriff's assessment found no known issues with the facility's air filtration system. But the grand jury learned that during the Santiago Canyon fire, staff members had to wear breathing masks for four to six hours because of smoke in the building.

A temporary filtering solution was expected to be installed last month, but the Sheriff's Department could not confirm Tuesday that it had been done.

It was not the first time a grand jury has examined the operations center. In 2001, a panel found that dispatchers handling emergency calls in the sheriff's patrol areas suffered from fatigue and stress, often because they skipped mandated work breaks to keep up with the large volume of calls.

Other grand juries have focused on the facility's ability to withstand an earthquake.

During a disaster, the center is the hub for county emergency communications. It is a critical function and "must not fail," the grand jury said.

The operations center was examined after discussions with current grand jury members and sheriff's managers raised questions about the center during a prolonged emergency activation, the report said.

The center opened in 1993 and was designed to house a small staff. But as the department grew, so did the facility. In September, it had 135 full- and part-time employees. In an emergency, that number can grow by 100.

david.reyes@latimes.com