This comes from a joint resolution of Congress in 2001, which designated that each year American flags should be lowered to half-staff in honor of the National Fallen Firefighters Memorial Service.

Gov. Mike DeWine has ordered U.S. and Ohio flags on public grounds throughout some of the state be flown at half-staff.

Missouri Gov. Mike Kehoe orders flags to fly at half-staff on April 12 in tribute to 16‐year-old volunteer firefighter Chevy ...