Acoustical gunshot detection system developed at PNNL
A small, relatively inexpensive device could make the difference between life and death for some when a shooter opens fire in a school.
“It was due to Sandy Hook,” said Jim Skorpik, a chief engineer at Pacific Northwest National Laboratory in Richland. He came up with the idea for the technology to give schools added security after the devastating news of the 2012 elementary school shooting in Newtown, Conn.
By the time police arrived at the school, 20 children ages 6 and 7 and six adults had been killed and shooter Adam Lanza had killed himself.
Skorpik knew that PNNL had already developed a small, battery-operated sensor system for the military. He thought it could be adapted to notify authorities within seconds of an active shooter situation, whether in a school, work place or other public building.
He and his team came up with software that would add the capability to the sensor to detect gunshots room-by-room, developing a detector that could be built with parts that cost about $100.
The acoustic gunshot detector is small enough to fit in the palm of a hand and light enough to attach to a classroom wall with a piece of double-sided tape. But it has a miniature computer on board sophisticated enough to assess whether a loud sound is a gunshot within two seconds.
It can tell the difference between a gunshot and other noises such as a popping balloon, slamming locker or firecracker with a high degree of accuracy. It also can determine what type of firearm was fired, and it relays the information by a wireless link to notify a first responder.
Tri-City-area law enforcement officials who volunteered to help test the device are enthusiastic about it.
Time counts, says Kennewick police chief
“The sooner the initial notification, the sooner police are dispatched and the more opportunity for survival,” said Kennewick Police Chief Ken Hohenberg. “Time counts in these types of mass casualty events.”
In mass shootings there is an initial disbelief, he said, based on information from recent summits he has attended.
People’s motor skills may not work well in such a frightening situation, and the simple task of calling 911 may be cumbersome. Or they may be in a position that taking out a cell phone and dialing could cost them their life.
With the system designed to have separate sensors installed in each classroom, hallway and areas like the cafeteria, police would have valuable information about where the shooter was within a school and possibly which direction he was heading, Hohenberg said.
Knowing what kind of situation they are going into will dictate what kind of weapon and what kind of tactic when they go into neutralize the threat.
Kennewick Police Chief Ken Hohenberg
The location information would be particularly valuable at a larger school, like a high school that might have several buildings on campus, helping officers go directly to the area where a gunshot was detected.
An arriving officer will know whether there might be more than one shooter and if the weapon is a handgun or a long gun like a rifle or automatic weapon that can be shot rapidly, as has been common in recent school shootings.
“Knowing what kind of situation they are going into will dictate what kind of weapon and what kind of tactic when they go in to neutralize the threat,” Hohenberg said.
Years ago officers would wait for a SWAT team to arrive, but now an officer in a nearby patrol car may enter the building immediately.
The Hanford Patrol and Kennewick Police Department helped test prototypes of the acoustic gunshot detector.
Local and federal law enforcement agencies helped test PNNL’s acoustic gunshot detectors by firing live rounds. The findings of lab and field tests were published in the peer-reviewed Journal of the Acoustical Society of America.
The Hanford Patrol fired different caliber fire arms and made other sounds, like dropping a stack of books on the floor, at the Hanford patrol training facility as PNNL developers checked the accuracy of the device.
The Kennewick police used the old Kennewick school administration building to fire shots, after developing a safety plan, Hohenberg said.
The noise was not enough to concern those outside of the building, further demonstrating the need for a gunshot detector, said an official with EAGL Technology, which holds one of the commercialization licenses issued for the detector.
Developing an accurate, low cost sensor
Skorpik’s goal was to make a device that was affordable, easy to install and accurate.
He started out with a sensor that had been developed by PNNL and now is being used in the nation’s Hellfire air-to-surface missiles that have been deployed in Iran and Iraq.
The sensors record humidity, vibration and shock to monitor the condition of airborne missiles.
What Skorpik found appealing is they have a long battery life, have an on-board processor or miniature computer, and use a wireless link to transmit information. The sensors also have been adapted for the Department of Energy with acoustic capabilities to listen for intrusion into containers holding sensitive nuclear materials.
Researchers faced the challenge of developing a mathematical algorithm that could distinguish gun shots from other noises, and do it better than the human ear.
To the human ear, a gun and firecracker might sound alike.
Kannan Krishnaswami, PNNL technology commercialization manager
The sensor uses frequencies created indoors in confined spaces, like classrooms, that the human ear cannot hear, Skorpik said.
“To the ear a gun and firecracker might sound alike,” said Kannan Krishnaswami, the technology commercialization manager on the project. “But to this detector they are very different.”
Skorpik also wanted the detector to be easy to set up, developing a smart phone app to program it with basic information, such as the time and date. Emergency responders can be relayed a time stamp along with the location of the device detecting a gunshot.
The detector also has a memory chip to store information that could be useful after the incident as police investigate shootings, including those with multiple shooters involved.
Interest from commercial market
PNNL’s role is to tackle tough intellectual problems and then rely on private industry to turn the technology into products, Krishnaswami said.
Other products are on the market, including to monitor outdoor spaces. But PNNL officials believe its indoor acoustic gunshot detector has the potential to be sold at much lower prices that could make them affordable for schools and offices.
The acoustic gunshot detector has been licensed to commercial developers, including EAGL Technology.
No one has been killed through a locked door yet.
Jennifer Russell, vice president of security technology for EAGL Technology
It has incorporated it into a system with multiple capabilities. It can stream video live from the camera nearest where the gunshot was detected and automatically lock classroom doors within seconds.
“No one has been killed through a locked door yet,” said Jennifer Russell, vice president of security technology for EAGL.
The system also can activate a public address system and provide other mass communication. It could tell students on a college campus that a shooter is in one building and to remain in another building, Russell said.
She estimates that an elementary school could purchase a basic EAGL system using the PNNL acoustic gunshot detector for about $25,000.
“This will not work for every situation,” Krishnaswami said. But it does have the potential to limit casualties, he said.
PNNL physicist Michael S. Hughes and senior technician Eric Gonzalez worked with Skorpik to develop the acoustic gunshot detector.