But they might soon get a better handle on some of the hairiest situations with the help of a simulator being developed by Carnegie Mellon University.
For the past three years, professor Jesse Schell and teams of graduate students have been working on ''Hazmat: Hotzone,'' a networked, multiplayer simulator that's a virtual disaster drill for dealing with hazardous materials.
It's a cross between a first-person shooter like ''Doom,'' ''Half-Life'' or ''Halo'' and a role-playing game. It is designed to fill the gap between classroom or firehouse lectures and mock disasters, like one involving as many as 14,000 people scheduled Saturday in Pittsburgh.
''The best instructors explain something and then do a role-playing scenario,'' said Schell, a professor at Carnegie Mellon's Entertainment Technology Center. ''Usually the trainees in the classroom have to imagine it and what they may or may not do. It is sort of like the instructor is like a dungeon master, leading them through this.''
A prototype of the simulator has been tested by the Fire Department of New York and the Region 13 Task Force, a group that includes emergency officials from 13 southwestern Pennsylvania counties and Pittsburgh. When it's finished, Carnegie Mellon plans to provide the program free to firefighting training centers nationwide.
Teams of firefighters sitting at desktop computers and linked over a network find themselves dropped off for a call -- say, a reported chemical leak in a subway -- and have to find and evacuate people inside.
The victims show symptoms such as vomiting, facial twitching, convulsions, bleeding, clammy skin and nausea, which can give firefighters clues to what chemicals are involved. Firefighters can look at the victims, talk to them to try to figure out what happened and tell them to evacuate or follow them to safety.
Instructors set up the virtual disasters by placing victims, chemical leaks and fires throughout a factory, street corner or subway. They can also give the victims symptoms that progress over time. For a chlorine leak, for example, the victims would begin by coughing, their skin would turn blue, they would begin vomiting and eventually pass out and die.
Instructors can also change the scenarios on the fly, adding new chemical leaks, victims or even knocking out one of the firefighters.
''The more realistic you can make it, the better it is,'' said Alan Caldwell, senior adviser for the International Association of Fire Chiefs and a former volunteer fire chief in Fairfax County, Va. ''You're obviously not going to release some type of a hazardous material just to find out if people get it by dropping in their tracks. But as close as you can come to the real thing, the better it is.''
Caldwell called firefighters ''good visual learners.''
''They do it by hands-on and by repetition and that's what training is all about. Because you have to train the way you are going to play,'' Caldwell said.
In a report a year after the Sept. 11 terrorist attacks, the federation noted that most of the nation's first-responders _ firefighters, police officers and paramedics _ felt they didn't have enough training to handle a terrorist attack involving chemical, biological or radiological weapons.
Video games are a natural training tool, said Kay Howell, vice president for information technology for the Federation of American Scientists.
The U.S. Army and the Federal Aviation Administration, for example, already use video game-like simulators to train soldiers and airline pilots and save money.
The federation has advocated the development of video games to train first responders to deal with hazard materials situations and approached Carnegie Mellon to see if the concept would work.
''Many of them are highly addictive,'' Howell said. ''They do a good job of training someone at a level and testing them and there is good feedback. Generally you know if you have done something right or wrong.''
