CHARLESTON, S.C. - City ladder trucks should never roll without at least four firefighters onboard and protective gear should be updated, a panel recommended Wednesday in response to a furniture store inferno that killed nine firefighters.

In its list of about 200 recommendations, the panel also suggested the fire department prioritize training, better plan its implementation and identify trainers both inside and outside the agency.

The city put together the advisory panel after nine firefighters were killed June 18 in a blaze at the Sofa Super Store. It was the most U.S. firefighters killed in a single incident since the Sept. 11, 2001, terrorist attack on the World Trade Center.

The city said it already has formed safety committees to study breathing equipment and protective clothing worn by firefighters. It also added thermal imaging cameras to ladder trucks and implemented an earlier panel recommendation to have firefighters state commands clearly on the radio rather than use codes like “10-4.”

Mayor Joseph P. Riley Jr. said he hopes the report will make the fire department one of the country’s best. The recommendations will require “substantial additional investment in public safety,” the mayor said, though he didn’t have a cost estimate.

The mayor and Fire Chief Rusty Thomas met with firefighters Wednesday to go over the report.

“I’m ecstatic about everything in the report,” Thomas said. “We want to be better. I’m just ready to go.”

The department will work to get four firefighters on all ladder trucks and plans to hire 12 additional employees, Riley said. The department also is now making sure that two firefighters remain outside a burning building for every two going inside.

Riley said the city took issue with a recommendation to increase overtime pay “to provide a greater incentive for members to work additional hours when they are needed.”

The city will review its current overtime policies, which were set in the aftermath of a federal lawsuit between firefighters and the city several years ago, but a change cannot be guaranteed, he said.

State regulators fined the fire department $9,325 for violating safety standards in the furniture fire. The state Occupational Safety and Health Administration did not say that the violations led directly to the firefighters’ deaths, but cited the fire department for four violations, including one “willful” violation for having an inadequate command structure that could not ensure firefighter safety in an emergency.

The city has contested the citations and has asked for a hearing before state regulators.

Officials still have not announced a cause for the blaze, though authorities have said the fire began in a loading dock area. Employees have said workers took cigarette breaks in that area.

Local and state police agencies, as well as the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, are investigating the fire.

The city’s advisory panel will provide a detailed analysis of the furniture store fire, to be completed sometime next year.