The buzz is getting louder.More than 100 firefighters in at least four area departments have taken electric razors to their heads to support Renee Thomas as she fights cervical cancer.

Her story has touched hearts across the region.

Firefighters in Summerville, James Island and North Charleston have joined what is now three-fourths of the Mount Pleasant Fire Department.

The movement began two weeks ago when Mount Pleasant Fire Lt. Troy Thomas shaved his head in the station after hearing from Renee, his wife, that she had lost the last of her hair to chemotherapy. His entire shift went under the razor with him.

The Thomases woke Monday to a photo of nine St. James Public Service District firefighters posing with their bald heads.

It was particularly heartening because Renee had had a difficult night, Troy Thomas told them.

More than 20 Summerville firefighters were shorn Sunday and posed for a shot that also was sent to the Thomases.

That mass buzz cut started with a decision by a few firefighters on one shift and snowballed. On Sunday, haircutters from Sports Clips volunteered their time to whisk away the locks.

“There’s a few families in our department, whether they’re spouses or children, who have cancer,” said Assistant Engineer Spencer Stevens. Stevens, who has a family member with cancer, sent other firefighters an email asking for the show of support.

Meanwhile, every piece of fire apparatus and 199 helmets in the Mount Pleasant department now carry cancer awareness ribbons, too, Troy Thomas said, and people in other departments and the community are asking about taking part.

The growing movement is inspiring for Renee and others fighting the disease, he said.

“This is really raising lots of awareness to anyone fighting cancer within our organizations and out.”

Reach Bo Petersen at 937-5744, @bopete on Twitter or Bo Petersen Reporting on Facebook.