|The precision personnel locator (PPL) developed at Worcester Polytechnic Institute (WPI) uses a new technology focused on a radio frequency (RF)-based system that transmits ranging information to all similar units and to a triangulation receiving unit on a fire apparatus. Shown here, rapid intervention team (RIT) members use the system to locate a down firefighter in a test scenario. (Photos courtesy of Worcester Polytechnic Institute.)|
|WPI’s PPL can be seen attached to the back of the firefighter’s air tank (standing in front of the pump panel) at the Massachusetts Fire Academy during live testing last year.|
|Honeywell’s Pathfinder uses a modular system built into a PASS alarm, with two beacons that emit an ultrasonic pulse when the PASS goes into full alarm. A handheld tracking unit is then used to locate the Pathfinder on the firefighter in trouble. (Photo courtesy of Honeywell First Responder Products.)|
A number of manufacturers offer equipment or systems that identify where a firefighter is located within a building, but the trend in such systems is moving toward not only knowing where a firefighter is located but tracking his movements and identifying his location in three dimensions. Some intend to go even farther, passing situational awareness data and firefighter physiological information back to fireground commanders.
R. James Duckworth, a professor of electrical and computer engineering at Worcester Polytechnic Institute (WPI), says the Institute is developing a fireground environmental sensor system that includes both a precision personnel locator (PPL) and an environmental monitor that can give real-time flashover warning and advanced firefighter situational awareness.
The project’s goal, funded by a $1 million grant from the U.S. Department of Homeland Security’s (DHS) Federal Emergency Management Agency (FEMA), in cooperation with the U.S. Fire Administration (USFA), is to reduce the number of injuries and line-of-duty deaths (LODDs) from traumatic injuries while operating inside structures, especially those from burns, smoke inhalation, stress, and becoming lost or trapped.
“Because GPS doesn’t work indoors and inertial technology has some problems, we had to develop new technology focused on a radio frequency (RF)-based system,” Duckworth says. “With an RF system, we don’t get the drift of an inertial system where the firefighter may be standing still yet appears to be moving.”
Duckworth says each firefighter would carry a small radio-based transmitter about the size of a smartphone. “Each device transmits a time-multiplex scheme,” he points out. “One firefighter transmits the ranging system, it goes to the next firefighter, and around to all other units, out to a triangulation receiving unit on the fire truck that works out where the firefighters are located, and displays them in three dimensions.”
The prototype system is larger than Duckworth would like it to be, but he believes economies of scale and modifications will bring the unit down to smartphone size. Plus the unit has to be cost-effective ito be a deployable system, he notes. “Firefighters don’t need to carry lots of extra pounds of gear,” Duckworth says, “and the units can’t cost too much. We think each transmitter will run a few hundred dollars. The receivers are a bit more expensive, but fewer of them are needed for the fire trucks.”
Duckworth says WPI also is working to have the system give more information about the fire scene—environmental information about the fire and structure, as well as physiological information about the firefighter. “The systems we’ve developed have the capability of sending a data link of the firefighter’s oxygen saturation level, his respiratory rate, heart rate, temperature, and information if he’s lying down or moving,” Duckworth says. “We’re also looking at flashover protection, where the firefighter would carry a small portable device that would give about 30 seconds warning about the potential of a flashover.”
Duckworth says WPI is ruggedizing and waterproofing the PPL and environmental monitor and expects to have the final architecture completed and ready for extensive testing by fire departments next year.
Honeywell First Responder Products recently demonstrated a homing device for firefighters and is in the process of making modifications to it as a result of focus group testing by a number of fire departments, says Mike Schubert, Honeywell’s engineering R&D technology leader. “We did the demonstration at Loveland Symmes Fire Department in Loveland, Ohio, and brought in fire departments from Kentucky, Indiana, Ohio, and Pennsylvania to take part in it,” Schubert says. “We also used them as a focus group to get feedback about how they’d like to see the homing device changed.”
Schubert notes there are currently devices on the market of the homing variety, but that “everything out there has some limitations in rapid location and retrieval of a firefighter in distress.” Honeywell’s homing device does things differently, he says.
“The technology we’re using allows the rescuer to essentially look through walls and materials that would tend to block the signals other devices use,” Schubert says. “It can actually see through concrete floors, both above and below the unit.”
Honeywell envisions the unit the firefighter wears, when it moves from the prototype stage, will be about the size of a matchbox or pager, while the rescuer would carry a portable handheld unit. “This technology operates in a radio spectrum where you don’t tend to get interference that standard RF or ultrasonic devices are prone to,” Schubert notes. “So, it is less impacted by the walls, floors, and steel outer shell of a structure.”
Honeywell already has a beacon-type location system available for firefighters, in the form of its Pathfinder, integrated into its SCBA. Jeff Shipley, Honeywell’s senior product manager for SCBA, says the Pathfinder is a modular system built into the PASS alarm, with two beacons on the back and one on the front of the PASS. When the PASS goes into full alarm, the beacons send out an ultrasonic pulse that moves through any nonsolid areas, even under doors. “[Firefighters] use standard operating procedures (SOPs) of following the hoseline to the firefighter’s estimated position because they need to get in the general area,” Shipley says. “They then use a tracking gun about six inches long, four inches wide, and an inch thick that can be clipped onto bunker gear. The beacon takes the rescue team the rest of the way to the firefighter.” The tracking unit provides both visual and audible readout, Shipley adds.
Honeywell also makes exit and auxiliary beacons to be used for firefighter location. “A rapid intervention team (RIT) can leave an exit beacon by the door and auxiliary beacons like bread crumbs, dropping one every 50 to 75 feet,” he says. “When they find the firefighter, they follow the beacons back out.”
Mike Petersen, director of product management for Motorola Inc., says his company makes a portable radio—the APX series—that can be paired with a location device to create a seamless system.
Motorola partners with TRX Systems Inc. and its Sentrix location device that computes 3D location, movement or nonmovement status, posture, and manually initiated alarms. The Sentrix unit is approximately five inches long, four inches high, and 1½ inches thick.
Petersen notes that TRX Systems is working on reducing the size of the unit. “To pair the devices, we bring the APX 7000 to within a half inch of the Sentrix unit and they set up an encrypted link,” Petersen says. “Once paired, they are locked together until you break down that link.”
In addition to pairing with the Sentrix, Petersen says that APX radios have accelerometers built into them. “If a firefighter is down, the radio fires off a signal and gives him an open mike,” he says.
Jim Reid, product manager of Harris Corp., says his company’s Unity XG-100P portable radio has built-in GPS-enabled situational awareness that enables user position to be sent securely over the air for personnel position tracking and rapid response for emergencies. The information, according to Harris’s specifications information, can be received by other Unity radios and displayed directly on screen for tactical situational awareness of all radio users.
“The Unity radio has a color display with multiple modes of operation when it comes to GPS reporting,” Reid says. “The primary method is via the full-color display, which allows the user to view units up to a range of 20 miles. The range of the display can be changed to suit the operational scenario the user is in.”
The second mode of operation, Reid notes, is connecting the Unity to a tablet or PC that runs a GPS application. The Unity supports Harris’s Falcon Command GPS application, as well as Google Maps. In addition, the Unity can send location reports over the air to a central host or can send the data to a local display via radio or serial connection.
Mike Brookman, president of Interspiro, says his firm’s SCBAs have a location feature built into the PASS alarm called the SpiroPulse. “It’s a hidden feature inside our electronic module and there’s no obvious indication to the firefighter that it’s there,” he says. “When the PASS goes into full alarm, the module activates an ultrasonic pulse that’s unaffected by the structure.”
Brookman points out that the module uses two emitters, one on each side of the air cylinder, with the cylinder acting as a resonator or amplifier for the ultrasonic pulse. He says the SpiroPulse, introduced late this summer, is derived from technology made by Summit Safety. “A RIT would have a small handheld unit that can be attached to a thermal imaging camera to sweep with a pulse sensor to determine the strongest ultrasonic signal,” Brookman says. “The locator unit will tell them the best path to the victim, even if he’s behind a wall.”
ALAN M. PETRILLO is a Tucson, Arizona-based freelance writer and is a member of the Fire Apparatus & Emergency Equipment editorial advisory board. He served 22 years with the Verdoy (NY) Fire Department, including in the position of chief.