SALEM — Public safety officials simulated a small explosion and fire in a commuter rail car filled with volunteers in Halloween costumes Sunday morning, part of a federally required annual drill.
A passenger in the last train car supposedly set off a small commercial firework while the train was in a tunnel near the Salem commuter rail station, said Randy Clarke, senior director of security and emergency management for the MBTA. About 120 civilian volunteers acted as if the firework ignited a seat cushion and filled the car with smoke.
“We wanted to get the police responding thinking it was terrorism, without it actually being terrorism,” Clarke said.
Officials started planning the exercise in March, before two bombs killed three people and injured more than 260 near the finish line of the Boston Marathon, another large and iconic Massachusetts event.
Planners picked the scenario because it would set off a fire department response and a police investigation, Clarke said. They chose Salem on Halloween because large groups come to the city for the holiday, and the tunnel near the station because it makes the rescue more complicated — ambulances and fire trucks could not pull right up to the train.
Workers from the commuter rail, Transit Police, the Salem police and fire departments, and Massachusetts Department of Transportation participated.
Thick gray vapor, generated from a smoke machine in the back of the train car, spread into the tunnel as passengers walked by the tracks to safety. Some wore Halloween costumes, in the spirit of the exercise, but others wore shorts and T-shirts to fend off the summer-like heat.
Seven people had simulated injuries, assigned ahead of time, from a head contusion and broken bones to minor burns and smoke inhalation. Four were considered serious but none were critical, Clarke said. There were no real injuries.
The Department of Homeland Security funded the drill, projected to cost about $10,000.
In the coming weeks, officials will gather information from the police officers, firefighters, and civilian volunteers who participated, looking for ways to improve their response in a real emergency.
Salem firefighters, for instance, discovered their radios did not get good reception in the tunnel, said firefighter Richard Thomas. They also figured another entrance to the tunnel might be an easier way in if there were a real emergency.
“That’s the beauty of the drill,” Thomas said. “We can find easier access points.”