By Keith Bowers
Police1.com Editor
Navigating intersections can be the most dangerous and time-consuming part of emergency response in law enforcement, and when lives are potentially at stake, every second counts.
Statistics bear out the fact that behind the wheel is the most dangerous place for law enforcement personnel. During 2007, more officers were killed in traffic-related incidents than from gunfire or any other cause of death.
Police-driving expert and Police1 columnist Capt. Travis Yates of the Tulsa Police Department says it can take as long as 30 to 45 seconds to clear and get through an intersection in the worst conditions.
“We see a lot of collisions in intersections with first responders,” Yates says, noting that side-impacts are common in intersections and also the most deadly.
A company called Priority Green aims to shorten response time while keeping officers safe by literally giving them the green light.
The concept is called traffic-signal pre-emption: Devices mounted on cruisers let the cars electronically communicate with signals as they approach, changing the officers’ light to green or keeping it in that position if it’s there already.
Depending on factors including weather conditions, terrain and the type of device used, the optically based systems can have a range of close to half a mile, according to Priority Green President Eric Canfield.
“All we’re looking to do is give them one more advantage,” says Canfield, whose West Chester, Pa., company is one of several making such devices.
Yates says pre-emption makes a lot of sense for law enforcement, noting that depending on the distance and number of intersections to be navigated, it can lessen response time by 5 to 7 minutes.
“And that could be the difference between life and death,” says Yates. “The quicker we get officers there, the more likely we are to catch someone or save someone from further harm.”
In order for pre-emption to work properly, traffic signals must be outfitted with a detector and a “confirmation light” that illuminates to tell the officers that the signal was received. Canfield points out that the equipment isn’t that noticeable, and a lot of people have probably seen it but not known what it was or thought much about it.
Communities across the nation have been installing such equipment at intersections to varying degrees in recent years, Canfield said, and regulation of the systems differs by state.
He estimates that between 50 percent and 60 percent of intersections in the United States are outfitted for pre-emption. Suburban areas are the most common place to find pre-emption technology, Canfield said.
The two manufacturers of pre-emption and receiving equipment are 3M and Tomar, Canfield says, and Priority Green transmitters are compatible with either system.
Canfield says the system has built-in measures to minimize confusion and missteps at intersections by civilian drivers.
Each state has a protocol for “lockout time” – the time between when a signal changes to green and when it can change back to yellow and then red. This, Canfield explains, is because when a driver gets a green light, he or she tends not to look at the signal again for 3 to 5 seconds.
What’s more, the confirmation light not only tells officers the system has been activated but it also tell motorists that something unusual is afoot, and they’re more likely to be alert and notice emergency vehicles.
“It really gives the public a chance to do what’s right,” says Yates.
Yates stresses that any department implementing pre-emption should make some effort to educate the public about the system.
This also applies to emergency responders. Although Priority Green makes it easier to get through intersections, it’s not a guarantee that all is clear, and officers should never assume as much.
Many police departments restrict use of pre-emption to vehicles that are using lights and siren, Canfield says, and some cities and counties restrict their use to fire vehicles.
With noise-reduction technology in late-model vehicles as well as the prevalence of tinted windows, police and fire crews are already at a distinct disadvantage with regard to being noticed compared with 10 or 15 years ago.
Numerous local, state and federal laws prohibit the use of pre-emption technology by the general public, and Priority Green sells its pre-emption products only to entities authorized to use them.
One manufacturer, Canfield says, sold devices to anyone who would pay, leading to stricter penalties for possession.
To departments that want to invest in pre-emption technology, Yates advises considering the cost of maintaining the equipment on vehicles.
To this end, Canfield says, Priority Green products are easy to install and service, fitting numerous places including inside newer low-profile light bars.
He said they also have built-in self-diagnostics, going through a number of checks on startup and repeating several while running.
“The diagnostics, more than anything else, is to relieve the burden … on people who have to maintain their own vehicles,” Canfield says.
If something is wrong, a light near the activation switch will flash at varying intervals depending on the problem.
“You want to know if you’ve got a problem,” Canfield says, “because you’re going to drive differently if you’ve got a problem.”
Priority Green will keep traffic signals in place as long as an officer needs, but it also has an automatic shut-off option that activates when a vehicle stops.
This feature can be wired to brake or transmission lines, but if doing so voids vehicle warranties, Priority Green has an optional module that lets the system “get to know” a vehicle and when to shut off.
Canfield says the average price to outfit a cruiser with a transmitter is $500 to $700, and Priority Green products start at less than $400.
“The use of these ought to be more common than it is now,” Yates says. “The communities that don’t have them should be the exception, rather than the other way around.”