While sweeping through the plant searching for wounded, the firefighter shut a door, isolating the source of the leak. In doing so, he left the maintenance worker for dead.
The firefighter, who also is a trained paramedic and registered nurse, had checked for a reaction from the worker and found none, or firefighters would have done everything they could to help, said Deputy Chief Richard Kipe with the Hagerstown Fire Department.
"In some cases, it's just so obvious the person is dead or is going to be dead in a few seconds," Kipe said.
"You can't save everyone," said John Bentley, co-chairman of the Local Emergency Planning Committee that organizes the annual mock disaster.
By closing the door, the firefighter saved more lives by isolating the source of the sulfuric acid, he said.
Annual staged disasters allow emergency personnel to determine whether they are truly prepared to handle a disaster, Bentley said.
Saturday's disaster went reasonably well, said Kipe. Emergency personnel attended a critique of the disaster on Saturday afternoon. The critique was not open to the public.
Similar to many emergency calls, the first to arrive at the plant shortly after 8:30 a.m. was a fire truck manned by a single firefighter.
The firefighter tried to calm a hysterical woman who was screaming about her friends in the plant and in the nearby operations building.
Students from Hagerstown Junior College's radiology technician program portrayed the wounded, including plant employees and members of a tour visiting the plant.
The city-owned plant produces pellets, which are a byproduct of the sewage treatment process that can be used for fertilizer.
When more firefighters arrived, the hysterical woman was screaming at firefighters outside the plant to do something.
"What are you doing? You've got to get in there to help them. You're taking too long," she screamed.
Despite the woman's screams and complaints, firefighters did the right thing by not rushing into the building, where they knew a chemical leak had occurred, said Hagerstown Fire Chief Gary Hawbaker.
"The worst thing you can do is kill more people," Hawbaker said. Washington County Hazardous Incident Response Team members protected themselves by putting on jumpsuits, oxygen masks and sealing off exposure points with duck tape.
As required by law, the pellet plant and other manufacturers are supposed to have available a list of chemicals on hand, what reactions they can cause and how to treat them, Hawbaker said.
Fake blood, burns, flour and smoke were used to simulate real wounds and chemicals.
Emergency personnel treated 26 wounded, including two firefighters who made mistakes that would have caused them to be hurt in a real disaster, Kipe said.
One firefighter entered the plant without breathing apparatus and the other slipped on a ladder while trying to rescue two wounded from a pit, he said.
The latter firefighter turned out to have hurt his back for real in the fall and was treated at Washington County Hospital and released, officials said.
All wounded were taken to the hospital, where more than 100 medical personnel were on hand to "treat" the wounded, said Les Stoner, the hospital's security director.
One wounded person who had driven to the hospital after the accident was treated in a special room so the hospital wasn't contaminated by hazardous chemicals, officials said.
All other wounded were scrubbed clean of hazardous materials before being sent to the hospital. If it had been a real hazardous incident, the victims would have been stripped and cleaned, Bentley said.
Saturday's exercise had a three-hour limit. If it had been real, after taking care of the wounded officials would have secured the plant, begun investigating and called state safety investigators, Kipe said.
Counseling also would have been available for emergency personnel, he said.
Also participating were Community Rescue Service, Funkstown Volunteer Fire Co. Inc., Volunteer Fire Co. of Halfway, Md., Inc., Clear Spring Ambulance Club Inc., Washington County Civil Defense and Washington County Fire and Rescue Communications.