'I need a volunteer," Richard Johnson announced to the high school students visiting the Bakken Museum in Minneapolis, standing before a display of odd looking instruments. "One who's really brave, has a high threshold of pain and no fear of death."

Johnson, himself a Bakken volunteer, was joking, of course. He cheerfully demonstrated the arcane electrical gadgets, and the students suffered nothing more shocking than some low-voltage tingles and upended hair.

Though rarely required to risk life and limb, museum volunteers like Johnson play a crucial role. Without their unpaid efforts, it's safe to say, many museums would not survive.

"Museums have always done more with limited resources, and one of the keys to making that possible is the dedicated support of millions of energetic volunteers," said Ford W. Bell, president of the American Alliance of Museums.

Minnesota's museum volunteers contribute an estimated 1.1 million hours a year, ranging from performing in costume to changing light bulbs, according to the Minnesota Association of Museums. The average museum has just two paid staffers. Nearly a third of the state's museums are operated by volunteers alone.

Johnson, a 68-year-old retired fire chief, contributes about 400 hours a year to the Bakken, earning the nickname "Mr. Awesome" (says so right on his nametag). After 13 years, he has accumulated knowledge ranging from the Rosicrucian beliefs of the man who built the museum's Lake Calhoun mansion, to the "doctrine of signatures" philosophy (the use of plants to treat body parts whose shapes they resemble) behind its garden design.

"That's what I love about this place — I learn probably more than I teach," Johnson said.

Volunteers often enjoy giving back to their communities. "I wanted to do something for the town, kind of return what they'd given to me growing up here, with a high school education and a good start in life," said Dean Vikan, 74, who retired in his native Fosston, Minn., and helped assemble the East Polk [County] Heritage Society's museum.

Frank White of Woodbury, a member of the Minnesota State Historical Records Advisory Board, creates projects around personal interests, including the Minnesota black baseball league. Recently, he worked on an informational plaque for the Dred Scott Playfield in Bloomington, named for the famous slave who unsuccessfully sued for his freedom and lived for a time in nearby Fort Snelling.

"There are places here that we go by and we don't have a sense of those pieces of history, of the importance of African-American contributions to Minnesota and this country," said White, 67.

For Sonja Thune and Verne Enestvedt, lead volunteers for the Sacred Heart Historical Society's museum, it's all about helping others, "seeing their excitement when we connect them to a distant relative," said Thune, 59. An experienced genealogy researcher herself, "I want other people to feel that adrenaline rush."

And volunteering can be fun, said Alisa Peterson, coordinator of volunteers for Heritage Village in Dakota City, Minn., which relies on hundreds of historical re-enactors.

"When you put this costume on and the ladies are in their long dresses and their pretty hats, gentlemen are in their suits and their nice hats, the gentlemen tip their hats and the ladies bow their heads," she said. "It's kind of like being in a different little world for a while."

Katy Read • 612-673-4583