Confronting Active Shooters

Five tips for implementing shot detection technology

According to a recent report from the DOJ and FBI, there were 27 active shooter incidents in the United States in 2018, resulting in 85 deaths and 128 injuries. Of these incidents, 16 occurred in business environments, five occurred in educational buildings and two occurred in healthcare facilities.

These situations are differentiated from other gun-related situations because the FBI recognizes that in an active shooter situation, law enforcement and citizens have the potential to affect the outcome based on their responses. To aid law enforcement response and help reduce the impact of incidents, security and life safety technology providers have recently started offering gunshot detection systems.

Today’s schools, businesses and healthcare campuses are employing indoor shot detection to reduce or eliminate delays and errors common in victim- or witness-initiated responses to active shooter incidents. Adding this technology to a campus life safety system can help shorten the duration of an active shooter event.

While an active shooter incident is something that everyone hopes never occurs, all campuses should have a response plan and the technology to deal with the situation appropriately and quickly. In order to select and implement the most suitable technology for a building or campus, it is important to consider the following five suggestions.

1. Choose the System Most Appropriate for Your Building Layout

Some shot detection systems use single-factor acoustic verification to detect gunshots. Acoustic detection uses sensors to capture a sound. Then, it develops an acoustic signature and uses computer-based signal processing to validate if the sound is a gunshot. This data is then used to determine the precise location of the shot.

Other systems use multi-factor authentication, where two or more sensing technologies are grouped together. These technologies can include the acoustic signature from a muzzle blast and/or from the shockwave of a bullet passing through the sensor field, changes in barometric pressure triggered by a shockwave, an optical flash/infrared signature from the ignition of explosive gasses in the ammunition propellant and comparison of the acoustic signature against an audio library of previously recorded gunshots.

Unfortunately, multi-factor authentication can fail to recognize an active shooter event if one type of detection is not authenticated due to the configuration of the space. For example, if an active shooter system requires both acoustic and muzzle flash authentication, wall sensors will pick up the gunshot, but muzzle flash may be masked by partitions or walls separating cubicles, offices or classrooms. While acoustic sensors can detect sound through walls and corners, infrared sensors can only pick up flashes within its line of sight.

2. Understand the Potential for False Alarms

The goal of multi-factor authentication is to reduce the number of false alarms by providing dual—or even triple—sound authentication. However, it can be a costlier solution because more sensors may need to be used. There is always the potential for false alarms regardless of the technology employed. There are single-factor systems with a lower false alarm frequency than some multi-factor systems in the marketplace today. It’s important to discuss the potential with the system providers and ask them how, and against what conditions and catalysts, their systems have been tested.

With single-factor acoustic detection, computer-based signal processing helps increase precision by analyzing a sound to determine if it’s an actual gunshot or just another sound with similar characteristics. For example, a cymbal crash from a drum set, which could be found in the music department of many campuses, has been found to trigger false alarms. Ongoing testing allows developers to refine algorithms and rule out these potential false alarms.

It is also important to consider that not every false alarm is necessarily a bad thing. In fact, it is arguably preferable to react to a false alarm than to have a system fail to identify an actual gunshot.

3. Know Best Practices for Sensor Placement

Acoustic sensors are most frequently mounted in ceilings or on walls. The range of sensors varies by manufacturer and depends on the acoustical characteristics in the space, like reverberation and sound absorption properties. Even the shooter’s body can create an acoustic shadow when shooting forward with their back facing the sensor.

While there is no limit to the number of sensors that can be placed throughout a building, budget concerns are forcing campus facility managers to focus their investment on placing sensors only in potentially high-target areas.

Some recommend placing sensors in areas where large numbers of people congregate like cafeterias, gymnasiums or auditoriums. However, this is not necessarily where the first shots take place. Other variables, including building access, approach, motive and the shooter's actions all play into the location of the first shots. Entryways and hallways may be the most effective areas to detect first shots.

It is important to note that system design will never be able to cover 100 percent of a building. This technology should be part of a comprehensive campus safety plan developed by security professionals. When determining what system will best fit your requirements, ensure the technology provider gives you a clear system design illustrating areas of coverage. Above all, involve your local law enforcement and stakeholder emergency response agencies in the decisionmaking process.

4. Pick System Offering Communication with First Responders

Active shooter events present numerous challenges for first responders and emergency staff. Communication of escalating events between 911 and witnesses can be both confusing and erratic, which can delay on-site response. This is compounded by the fact that active shooters can move at a fast pace throughout the building— making it even more difficult to track the shooter and prolonging the event.

Early detection can trigger a host of responses including alerting students, staff, patients and other building occupants to the location where shots were fired while triggering building alarms, emergency notifications, evacuation and sheltering procedures.

Recent tests have shown that shot detection technology with automatic emergency communication enables law enforcement to respond and mitigate a threat up to 60 percent faster. Today’s leading gunshot detection systems even offer map-based graphical user interfaces that display the location of the shooter to building occupants and law enforcement, as well as display audio and video of the incident. The systems provide safety and evacuation instructions while communicating with emergency services and mass notification systems, prompting a quick response by law enforcement.

Acoustic detection can also indicate the number of shots fired and the cadence at which they were released, giving insight into the type of weapon the shooter is using. This data is sent to security, law enforcement, hospitals and fire service to enhance their overall strategic picture of the situation and aid in response.

5. Look for Integration Features

To maximize effectiveness, it is important to select a gunshot detection system that supports multiple integration options, including video feeds from existing CCTV and intrusion systems, mass notification systems, access control systems and panic button/ manual initiation systems.

In the future, the integration of shot detection into existing life safety systems will enable facilities to leverage the infrastructure already in place. After detection occurs, mass notification to occupants, first responders and law enforcement can be sent through the same systems used for fire detection. Like all life safety systems, redundancies will be built into shot detection technology to ensure continuous uptime.

While no technology or planning will ever eliminate active shooter threats, it can significantly shorten the duration and lessen the impact of the event. Advancements in shot detection give occupants, emergency management and first responders valuable seconds to react to active shooter events and, in turn, potentially save lives.

This article originally appeared in the September/October 2019 issue of Campus Security & Life Safety.