Anyone passing by Campanelli Stadium on Tuesday afternoon might have thought the place was under attack, with first responders in bulky protective hazardous materials suits filing in and out.

And that’s exactly what the men and women in those suits were supposed to be thinking, too. Public safety agencies from across the region gathered at the stadium for a massive hazmat incident response exercise that was months in the making, according to Brockton Deputy Fire Chief Kevin Galligan.

The training was designed to simulate a chemical attack on a crowded stadium during a concert, sporting event or rally, he said.

Such incidents have become more common over the last few years, which have seen bombings at arenas in Paris, France and Manchester, England, and, mostly recently, the worst public shooting in the nation’s history at a country music festival in Las Vegas, Nev.

“This was a regular training day for the state Hazardous Materials Response Team, but we invited the Brockton Fire Department, the police department, Brockton emergency medical services, the state police bomb squad, Brockton Emergency Management, and the National Guard to participate,” Galligan said.

Fifty members of the Brockton High School Junior Reserve Officer Training Corps also participated, taking on the role of eventgoers and allowing the first responders to practice screening visitors on the way in and rescuing people once the attack had happened.

“The whole drill wouldn’t have been possible without them,” Galligan said. “They were well-disciplined, well-led and did a great job.”

Participants also practiced locating radioactive materials in the venue, which were brought in, handled and hidden by a radiation expert. Continue reading.