Mitigating active shooter situations at the K-12 level doesn't have to be expensive

Available security technology can potentially save lives and still be cost-effective

A rash of recent school shootings has renewed the call for better security. The problem is that K-12 schools often don’t have the budget to match their growing security needs. But there are steps every district can take now to make schools safer, and they don’t need to spend lot of money to do it.

Every K-12 school in the U.S. should have the $400 solution, which is outlined below, in their reception area. This is a simple solution that is still based on cutting-edge intelligent technology. Having this $400 solution could save a life, if not dozens.

Detection, Decision and Notification

First, we have to realize that there is no definitive way to entirely  stop school shootings. We must concentrate, instead, on detecting and acting on a situation once it happens.

It doesn’t matter how much security a school puts on fences, doors and lobbies. These measures may prevent some people from getting in, but it can’t stop everyone. Someone intent on doing harm can easily tailgate a person with authorized entry through a controlled door. Imagine – a parent is buzzed into a school, and the bad guy walks in behind, draws a gun and starts shooting.

In active shooter situations, every second matters; and while it may not be possible to stop every crazed gunman from entering a school, technology can provide instant situational awareness making it possible to take immediate, potentially-life saving action.

The kneejerk reaction might be to consider a gunshot detector, but for cash-strapped schools, this would be cost prohibitive. Typically deployed in city centers, these detection devices use sophisticated triangulation to pinpoint the direction of a gunshot, but cost from $50,000 to $100,000 each.

A school’s needs are much more modest. In an active shooter situation, it’s not necessary to know precisely what direction a gunshot is coming from. But officials would want to be instantly alerted if there’s a very loud sound, suggestive of screaming or gun shots.

Fortunately, there is a cost effective way for cash-strapped schools to accomplish this.

For several years many camera manufacturers have been adding more intelligence to their edge devices. Many are now configurable, like a mini self-contained computer, and can sense loud sounds through built-in microphones, ignore certain frequencies, make decisions and then notify those who need to know.

In an active shooter situation, there are three basic capabilities required:

  • Detection (loud noise is detected)
  • Decision (determination that it is potentially an active shooter situation)  
  • Notification (immediately alert the proper authorities, administrators and other stakeholders).

Let’s look at how this can be accomplished using a typical $400 IP camera. Remember, the concept is very simple and so it should be doable with many models and brands. In this case, it was tested on one IP camera model and brand.


Many IP cameras have a built-in microphone (or alternatively a school can use an external mic via the line-in port). The idea is to use this microphone for detection. Audio detection can be configured in three ways to ensure the highest probability of detecting an active shooter situation.

  1. Threshold: this is the level above which the alarm will trigger, so it should be set quite high. It is easy to test  – just have someone talk, shout and then scream and decide at which point you want an alarm to be generated. This will minimize false alarms. I also recommend that schools team up with their local police, who should be able to test the system using blanks.
  2. Sensitivity: this is how quickly the camera responds to changes in the sound environment, so it should be set fairly high. You want the alarm to trigger the moment the shot is heard, and not have to wait for a long period of high noise before the alarm trips.
  3. Tonal range: certain groups of frequencies can be selected or deselected to eliminate false alarms. To detect both gun shots and screaming, all frequencies should be activated. If it is just for gun shots, I recommend staying in the lower range -- 300Hz – 1 kHz.
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