Hoping to prevent the theft of materials, Carroll County Public Library officials had security systems installed in four of the county branches last week.
Scott Rinehart, CCPL's technical support administrator, said Westminster, Taneytown and Eldersburg branches received the systems build by Knogo North America, Long Island, N.Y., Thursday.
The North Carroll branch in Greenmount had a system installed Friday.
The detectors, purchased for a total of $41,200, consist of panels near the doors activated by small metal strips hidden within the materials.
A properly checked-out item will have been desensitized by the attendant. Otherwise, an alarm will sound as the patron leaves the building.
"We were expecting them to work well, but they work extremely well," Rinehart said. "I'm very, very pleased with them."
Due to a lack of space in the present facility, Mount Airy will not be getting a security system until the construction of the new building, he said.