MAINE – Fires and explosions have long been threats to Maine’s lumber and paper mills. In April 2020, a pulp digester exploded at the Androscoggin Mill in Jay. Some people were treated for respiratory issues, but no casualties were reported. The paper mill closed permanently in 2023. At Irving Forest Products in Dixfield, an explosion and fire in May 2021 damaged a machine used to move wood chips. No injuries were reported in either incident. “The fuel load at a lumber mill is exceedingly high,” said James Graves, director of the Maine Fire Service Institute, which provides and certifies firefighter training programs. “There are so many variables, they happen regularly all over the state and beyond.” But Graves said relatively few are as tragic as the fiery explosion at Robbins Lumber Inc. in Searsmont that injured 12 people and killed Andrew Cross, 27, a member of the Morrill Volunteer Fire Department. Eight were still hospitalized Tuesday.