On an indoor set at the Prince William County Public Safety Training Center in Nokesville, fire and rescue technician Jill Sears assesses actor Justin Mohay’s artificial dark-red chest wound as he lies motionless on the ground; a tag around his neck indicates that he was shot in the chest. Firefighter/paramedic Adam Shannon is trying to clear a path for patients trying to get from the elevator to treatment areas set up outside the building. The area is blocked by foam-filled dummies marked with black tags: deceased.

“We’ve got patients coming down the elevator. Can we move these bodies out of the way, to the side?” Shannon asks a rescuer.

The two-story structure, strewn with actors and foam-filled dummies representing shooting victims, is filled with voices screaming out in pain or moaning for help. Cutting through the chaos are the overlapping voices of the dozen-odd rescuers in the building. “Can anyone else walk here? Keep walking, right over toward the door.” “It just hurts everywhere — nothing specific? Okay, what we’ll do is have you be patient and sit here for a minute.” “Ma’am? You got shot in the leg. Can you hear me?”

The 45 rescuers and 20 role players are participating in an all-day training simulation for Prince William firefighters and emergency medical service (EMS) providers. The simulation is an attempt to prepare rescue workers for a worst-case scenario they’ve never before encountered, a large-scale mass casualty event.

Today’s simulation: a shooting at a business that also houses a day-care center.

Rescuers treat patients in the triage area. The 45 rescuers and 20 role players are participating in an all-day training simulation for Prince William firefighters and emergency medical service(EMS) providers. (Bettina Lanyi/Bettina Lanyi)

The event is part of Prince William’s first large-scale countywide training for mass casualty incidents beyond the scope of fires and natural disasters. After tragedies such as the school shooting in Newtown, Conn., and the Boston Marathon bombings, Prince William and other localities are taking measures to prepare for the unexpected and unthinkable.

“We need to be prepared for anything at any point in time,” said battalion Chief Kim Pumphrey, who runs the sessions at the Public Safety Training Center. Pumphrey said that shootings with multiple victims “used to be a low-frequency type of incident, but unfortunately it’s becoming more and more common in the news throughout the world and right here — Virginia Tech, Boston, different areas. So it’s really imperative that we get all of our providers in the region on the same page so we can be prepared for anything that might happen.”

To that end, the center’s staff developed a nine-week training program this year for each county fire station, adapted from Northern Virginia’s recently updated Operations Manual for Multiple Casualty Incidents. After training at each of their respective stations, firefighter/EMS providers participate in one of six day-long casualty simulation sessions at the training center. Nearly all of Prince William’s career and volunteer fire and rescue personnel — 400 to 450 in all — will have attended a simulation by the end of the month.

Lt. Beth Kenavan, who serves on Dale City’s medic unit, describes the value of the mass casualty training: “You have to think on your feet, working under conditions that are different than those you’d encounter day-to-day. It’s definitely a good training to have. Eventually something’s going to happen at some point — we can’t think we have a bubble over Prince William County.”

“It’s helpful, because usually when you do a training, everything’s slowed down a little bit. This training is fast-paced, at call speed,” said Shawn Riley, a level-two technician who has served as a firefighter/EMS in Prince William for 15 years (in Prince William, all personnel are required to be certified both as firefighters and EMS providers). Riley said the role players help create a more realistic training scenario: “When you deal with a mannequin, the realism isn’t there. With role players, the people scream, and you have to be extra-careful with the role players because they’re real. It’s nice to have it as real as you can get.”

The training gives responders experience in working with a large number of rescuers from other jurisdictions at the same incident scene. “You can see all those big moving parts coming together, working together, and why it’s so critical to see that this person needs to communicate with that person and these things need to fall in place at these times,” Riley said. “So this is the perfect scenario for that. The point of [the training] is that when you’ve got a Prince William guy, a Loudoun guy, a Fairfax guy all working together, everyone knows what to do because we’re working off the same sheet of music.”

Despite the challenges of a large-scale event, however, creating calm out of chaos is an everyday job for rescuers. “Every day, when you have an incident, it’s a chaotic scene for anyone who’s calling 911,” Pumphrey said. “Whether it’s a stubbed toe, or they’ve cut their arm off, or their husband is lying on the floor in cardiac arrest. It is their worst nightmare, their worst emergency. Nobody plans on calling 911, so our role is always organizing the chaos, calming the chaos.”

“We train as real as we can,” Riley added. “We don’t sit around here. There’s a misconception that firefighters hang out, play checkers and all that, but we’re out there training. We’re always trained. So we’ll always be there, ready to go.”