The Representative Town Meeting has approved $200,000 for school security locks, but not before debating the effectiveness of the safety devices, particularly on doors with glass panes.

Members at Tuesday's meeting also expressed concern about who would have access to the keys to unlock the doors -- and, possibly, the vulnerability -- of the hundreds of students who congregate daily in school gymnasiums and cafeterias.

The RTM was told the school district would use the money to purchase 1,400 lock sets at a cost of $132 per unit, according to Elio Longo, the school district's business manager. They will be installed over the summer.

The locks were described as a "simple cylinder lock system" that would lock doors when they are closed. The only way to get back into that classroom from the hallway would be with a key.

That led RTM member Kristan Hamlin, D-4, a former prosecutor, to express concern that police or other first responders wouldn't be able to get into a classroom with its door closed in the event of an emergency. But Longo assured her that the would "share keys with first responders."

RTM member Arthur Ashman, D-7, brought up the issue of "doors that have glass on top of them" -- those that aren't completely made from a solid material. He said that doors with glass could allow access if the glass were shot out.

Hamlin agreed, saying there were windows on the front door at Sandy Hook Elementary School -- the scene of a massacre that claimed 26 lives in December 2012 -- and "the killer came in by shooting a gun at the glass door."

She said the locks won't provide much protection against someone with a gun. "All they have to do is shoot the glass and open the door," she said.

Longo said that, as an extra measure of protection, officials are looking into putting wire mesh on the windows.

Hamlin said she hated to "sound morbid," but another concern is that children could be locked into a room "with someone torturing them."

RTM member Jack Klinge, D-7, who made the presentation for the locks funding on behalf of the RTM's Finance Committee, said that, although classrooms would be secure, he was concerned about "large group areas," like the cafeteria and gymnasium.

He said that at lunchtime at Staples High School, "there are 600 kids in the cafeteria" or one-third of the school during each lunch wave.

RTM member Diane Cady, D-1, said she was troubled by how long it's taking to implement security measures, a program prompted by the Sandy Hook shooting, and asked what was going to be done about the "front and side entrances" of the town's schools.

"This is a careful, thorough, and deliberate process," said Board of Education Chairwoman Elaine Whitney. "It's taken a number of steps over the year" to get to this point, she said, adding that school officials have also taken other measures to make schools more secure.

While she didn't provide details, she later said the school system is looking at some combination of "policy, procedures and infrastructure."

RTM member Jeffrey Wieser said he thought "this is going to get expensive" as other security measures recommended in a report by the Kroll consulting firm are implemented. That $100,000 survey was arranged in the wake of the Sandy Hook shootings.

"This will be a big addition to the capital expenditure," Wieser added.

The locks funding, which will come from the town's capital and nonrecurring budget, was approved by the RTM in a 28-0 vote, with only Cady abstaining.

Longo said the town will be reimbursed $40,000 from a state grant.