SACRAMENTO — This year's fire season may turn out to be the worst "in the history of California," the state's top fire official said Wednesday.

"We are definitely seeing fuel conditions that we've never seen before, especially in Southern California, and the conditions are ripe for catastrophic fires," said Ruben Grijalva, director of the Department of Forestry and Fire Protection.

Realizing that fighting fires is no longer enough, the department has been concentrating its planning on preventing fires and doing things ahead of time to contain their spread, he said.

Grijalva was among about a dozen state officials and scientists who testified at a special legislative hearing to examine the state's preparedness for dealing with the anticipated disasters in the months ahead.

Recent data show that the most damage comes from the one-half of 1 percent of fires that escalate out of control, said state Fire Marshal Kate Dargan.

"We're beginning in this process to recognize that the speed of the fire spread and the ignitions of the structures is overwhelming the firefighting forces," Dargan said of the largest fires.

Recognizing this problem, the state firefighting agency has been focusing on preventing fires through safer development, Grijalva said.

It created a comprehensive fire hazard map, increased its outreach efforts and involved local governments in decision-making, he said.

He also noted that new building codes that require ignition-resistant construction will go into effect Jan. 1.

Ignition-resistant construction includes using materials that are not liable to catch fire, installing dual-paned tempered glass in all exterior windows and guarding against airborne embers, which can travel up to a mile.

Data from recent fires show that 97 percent of homes with 100 feet of defensible space and ignition-resistant construction can survive the blaze, Dargan said.

Defensible space is an area that has sparse vegetation and prevents the spread of the fire. It does not have to be clear-cut land.

Firefighting can save only 10 percent of houses in the largest fires, Dargan said. "To be effective, we have to keep the homes from burning."

Even though the new building codes will apply only to new houses, she said this marks "a watershed year" for firefighting.

The focus of new building standards and analyses of fire hazards is on housing development that abuts forests, grasslands and other wilderness.

There are 4,500 miles of "edge" between wildland and development in Riverside County alone, said Thomas Scott, associate director for the Center for Conservation Biology at UC Riverside.

While many homeowners want to live on the border of the wilderness, Scott said, such growth is often unplanned and creates many problems for firefighters.

He said many new developments are virtually indefensible against fires.

The hearing was called by Assemblyman Pedro Nava, D-Santa Barbara, who chairs the Joint Legislative Committee on Emergency Services and Homeland Security. Nava has proposed legislation to combine the state Office of Emergency Services and the Department of Homeland Security into a single, Cabinet-level agency.