Nearly three-fourths of the nation’s teachers say they personally would not bring a firearm to their school if allowed, but most educators believe armed guards would improve campus safety, a new survey showed.

Since the December massacre by a lone gunman in Newtown, Conn., many schools have hastened to add safety measures in an effort to prevent similar violence.

The most common step since the shooting at Sandy Hook Elementary School that left 20 first-graders and six educators dead has been ensuring that all doors are locked, teachers said.

Of the nearly 11,000 educators surveyed nationwide, most said they generally feel safe in their schools, but disagreed on whether their workplaces were safe from gun violence.

Nearly four in 10 school superintendents who responded said their schools were not safe from gun violence, slightly higher than the 31 percent of teachers who felt their schools were not safe.

January’s online survey was conducted by School Improvement Network, a for-profit company that specializes in professional development for educators and partners with schools, districts, and educators.

Some 72.4 percent of educators said they would be unlikely to bring a firearm to school if allowed to do so.

The company’s CEO, Chet Linton, said, given his company’s close ties with the education community, it felt the need to make sure teachers voices were brought into the debate over gun policy.

“We have a community of more than 900,000 educators that are part of our network, and as we watched the coverage of Sandy Hook unfold and politicians and other groups begin to respond to the tragedy, we were concerned that the country was not hearing from educators. They are the experts in the classroom,” Linton told CNN in an email.

School Improvement Network says its mission is solely focused on the business of education. The company said it has no affiliation with any gun control or gun rights groups.

The Connecticut shooting jolted the nation and prompted a new debate over gun control. Suspect Adam Lanza brought three weapons inside Sandy Hook Elementary school on Dec. 14 and left a fourth in his car, police said. The weapons taken inside were a Bushmaster AR-15 rifle and two handguns—a Glock 10 mm and a Sig Sauer 9 mm.

Since then, in Congress and state houses across the nation, lawmakers have grappled with how to curb the threat of gun violence without infringing on the constitutional right to bear arms.

Proposals in Washington would ban assault weapons, expand background check requirements for gun purchasers, and tighten loopholes to further keep guns out of the hands of the wrong people.

The politically powerful National Rifle Association has argued armed guards in schools could prevent shootings such as the one in Connecticut.

Wayne LaPierre, the NRA’s chief executive, raised the possibility the Newtown massacre might have been averted had the school employed an armed guard.

New York City Mayor Michael Bloomberg, a well-known crusader who has spent millions of his own money on gun control efforts, called the NRA’s idea for armed guards in schools “a paranoid vision of America.”

But teachers appear to disagree with Bloomberg’s assumption. Almost 90 percent said an armed police officer would improve safety in their schools, not make them less safe, according to the survey.

Educators also detailed ways that schools have improved security following Newtown.

Sample responses included armed guards, periodic vehicle patrols and in-person visits by police and volunteers to monitor doors.

Todd Sperry | CNN