"Students were injured in the chemistry lab," explained Dick Sloan, public affairs officer for the Army, one of the agencies assisting Tooele County Emergency Management for the disaster drill.

The shaking of the earth doused Grantsville High School drama club students with various chemicals and acids, which caused chemical burns on their faces and arms. Students were also told such chemicals gave them breathing difficulties.

Firefighters dressed in haardous materials suits escorted the mock victims into the Tooele County Mobile Decontamination Facility, where they were stripped down to swimming suits and thoroughly washed with water.

"It's kind of like a human car wash," said Mason Hill, ambulance director for Mountain West Ambulance.

He said in a real disaster, people would be stripped completely naked to get decontaminated, which he said always makes the students giggle.

After a thorough washing, the victims are dressed in paper coveralls and sent out to paramedics who determine the extent of their injuries — a mock triage — to determine what treatment they require. A colored band is placed on the victim's arm to determine the seriousness of their medical needs. A green band means walking wounded, yellow is serious, red is critical, black is diseased, blue means the victim is decontaminated, and orange means the victim was administered an antidote to a possible toxin.

The banding system was instituted from past disaster drills, according to Tooele County Emergency Management Director Kari Sagers.

"In the earlier days we didn't have a good way to track patients at a decontamination site," she said.

During past drills, rescue workers would decontaminate a victim multiple times because they had no proof the victim was decontaminated. The colors ensure all victims are treated as needed. She said the banding system makes emergency response more efficient.

After triage, the victims wait for proper treatment. Some are treated at the scene, some treated at the hospital, in this case Mountain West Regional Medical in Tooele.

At the hospital, another decontamination unit was in place in case any of the mock victims did not get decontaminated. A disaster team inside was mobilized to handle the emergency, from injuries to security.

During the drill, evaluators watch the performance of emergency workers. Their findings are compiled into a report, which is shared with the agencies, to identify areas that need improvement, according to Steve Horwitz of the Federal Emergency Management Agency.

"The whole intent is to make these folks better," Sloan said.

The drill date is known beforehand, but few know the scenario, according to Sloan. Not knowing will more accurately showcase the agencies' response to the disaster.

"It needs to be as realistic as possible," he said.

Sagars said it takes a year to prepare for the drill. She said separate agencies do their own drills throughout the year but this brings everybody together.

"I think it's gone very well today," she said.

E-mail: lwilde@desnews.com