Last week marked the six-year anniversary of the deadly mass shooting at Sandy Hook Elementary School in Newtown, Connecticut that took the lives of 20 children and 6 adults.

There were school shootings before the Sandy Hook event, and there have been school shootings after. According to Everytown for Gun Safety, a group formed in the wake of Sandy Hook, there have been 89 incidents involving gun fire at schools in the last year alone. But Sandy Hook represents a cultural touchstone in some sense, and is often cited in debates over how to solve the problem of mass shootings.

But what lessons have we learned since Sandy Hook?

Campus Safety Magazine identifies seven lessons from Sandy Hook. Among the most striking is the necessity to act quickly in the event of an active shooter situation.

Quickly implementing lockdown procedures undoubtedly saved the lives of many at Sandy Hook. Twenty of the victims where killed in or near two unlocked rooms. In the Marjory Stoneman Douglas High School shooting in Parkland, Fla. last year, 22 people were shot in the first 69 seconds of the incident. Speed is crucial, yet difficult to achieve in high-stress situations.

In crisis simulation exercises conducted by Campus Safety Magazine, school personnel miscalculated the time they would have to lock the door. It took between 30 and 40 seconds to find keys and lock doors in many cases, and up to a minute in others.

Part of the delay may be attributable to being able to quickly and accurately assess the threat.

Shot detection systems like Guardian remove the uncertainty and reduce time to act by automatically and accurately detecting gunfire and initiating response. Guardian uses acoustic and infrared sensors to detect gunfire. Guardian can integrate with systems to automatically lock doors the moment a shot is detected. That quick action can limit a shooter’s movement, and also limit the movements of potential targets, keeping them out of harm’s way.

Guardian can also be integrated with other systems, such as communication systems, to immediately alert authorities, staff and other key stakeholders the second a shot is detected.

Schools are recognizing the value of Guardian. For instance, schools in independent districts across Texas have chosen to install Guardian as part of a comprehensive school safety approach aimed at “hardening” schools unobtrusively.

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