But many library workers said they are more disturbed by the presence of cameras on the construction site than they would be if they could not see the work in progress.

"As far as a legal issue, an employer can probably do this, but as an ethical and moral issue, who would want to work like this?" said Karen L. O'Brien, also a representative to HUCTW.

"It's a slap in the face. They're saying 'This is our way of keeping you informed,'" said library employee Jeffrey Booth.

O'Brien said some workers are also concerned that the surveillance system may create safety hazards.

"If I was walking on a scaffolding and there was a camera watching me, I'd definitely be nervous," she said.

"[The cameras] are a waste of money," Booth added. "There are much bigger issues at stake."

Both Carens and O'Brien left messages in a suggestion box in the staff room, asking if the cameras were appropriate. But both said the responses they got over an employee e-mail list were unsatisfactory.