By Marielle Mohs

MINNEAPOLIS (WCCO) — There is a silent killer affecting Minnesota firefighters, and it doesn’t involve burning buildings, flames or smoke.

More than half of firefighter deaths are caused by heart attacks. This week, 49-year-old Howard Lake Fire Chief Daryl ‘Taddy’ Drusch died of a heart attack within 24 hours of his last emergency call.

READ MORE: Minnesota Weather: Severe Thunderstorm Watch Issued For Parts Of Minnesota, Wisconsin

“The St. Paul Fire Department is one of many Twin Cities fire stations that’s made heart-healthy changes to make sure none of their firefighters die of a cardiac arrest,” St. Paul Deputy Fire Chief Roy Mokosso said.

When Mokosso shows up to work each day, he hits the treadmill. After the department lost 38-year old Shane Clifton to cardiac arrest back in 2015, they made overall health changes.

READ MORE: Who Will Qualify For State's $250 Million In Bonus Pay For Front-Line Workers?

Deputy Fire Chief Roy Mokosso (credit: CBS)

“All of our firefighters, all 435 members, went through health and wellness classes this year,” Mokosso said. “Going from a sedentary state to having to be reactive, and on an emergency scene and having to make decisions, there’s stressors involved.”

Minnesota Fire Initiative President George Esbensen says the leading cause of heart attacks for firefighters happens when the emergency call goes out.

“The average American, if they’re going to get a heart attack, is somewhere in their late 50s, early 60s. Firefighters tend to be 10-plus years’ younger than that,” Esbensen said. “Maybe it wasn’t that particular call, but it’s a lifetime of calls, you know, that causes this, and that leads to cardiac issues.”

MORE NEWS: Driver James Blue Arrested In Orono Crash That Killed Mack Motzko, Sam Schuneman

For that reason, a Federal law was passed in 2003 that calls any heart-related death within 24 hours of a call a “death in the line of duty.” That’s important because it means that firefighters’ families will get better benefits.

Marielle Mohs