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|FAQ: General Questions
1. What does the Pathfinder™ system do?
The system consists of two parts, a Beacon, which transmits an ultrasonic homing signal, and a Tracker, which indicates the path to
the specific Beacon. Beacons can be used to identify firefighters, exit points, auxilary waypoints, and even childrens' rooms.
The Tracker listens for the specific signal from a Beacon and displays the strength visually with a bar graph and audibly by a series
of beeps. By scanning a room with the Tracker, much like scanning with a flashlight, and by moving in the direction of the strongest
signal, a disabled firefighter or exit can be rapidly located. One could think of the Beacon as a lighthouse and the Tracker as a your
eye (one that works well in smoke).
2. Why do you want to know the PATH?
Think of finding a firefighter as the process of solving a maze. When you sit down and try to figure out your strategy, you first
need to identify the start and finish of the maze. These two LOCATIONS are very useful, but they don't tell you how to NAVIGATE in
between. To do that, you need to have an understanding of what the PATH is like between the two points.
Now Look at the image to the right. The firefighter in trouble is at the location marked "X" and the Rapid Intervention Team (RIT) is
entering at location "A." If the RIT knows that the firefighter is in the middle of the building, they might be tempted to head in the
direction of door "D" and then "E." Unfortunately, that is the wrong direction to go.
What the RIT members really need to know is HOW to get to the firefighter, not just his location. In this example, the RIT
would have needed a tool that would tell them the PATH to get to the firefighter. The Pathfinder system is designed specifically for
this purpose. Since, sound does NOT go through walls, it is forced to travel through the door opening at "C", and down the hallway,
"B", to location "A." The Tracker tells the RIT to head inside, go down the hallway to the right, and head to the doorway (shown as
"C"). It then tells them where to go within the room, right to the firefighter.
3. Why not use radio frequency (RF)?
One of the apparent advantages of using a radio frequency (RF) approach is that some radio waves can penetrate walls, allowing a
firefighter to "see through walls." A SERIOUS PROBLEM arrises when you need to penetrate walls that the RF device is telling you to
go through. When a firefighter is low on air, you don't want to spend time breaching when you could be navigating the PATH to him.
Just imagine how long it would take you to cut through a concrete block wall.
Now consider the above example in question 2. The firefighter is at the point marked "X" and the Rapid Intervention Team (RIT) is
entering at location "A." An RF device would tell you to head straight through the wall to the firefighter. From the perspective of
the RIT members, they don' know how many walls will have to be breached along that route; it may be several. Even worse, if the RIT
does not have the appropriate (and heavy) tools, breaching may not even be an option. Knowing that going through the walls
may take more time than the firefighter has air, they might be tempted to head in the direction of door "D" and then, eventually,
door "E." As in the above example, that is the absolute WRONG direction to go.
4. Is Pathfinder a Thermal Imager?
No. A thermal imaging camera (TIC) allows a firefighter to see through smoke by sensing very-long-wavelength heat signals. If a
firefighter is disabled, a rescue team must search for the firefighter. Since the heat signals are not reflected very well by most
surfaces, TICs are essentially line-of-sight; that is, any obstacle between the TIC and the firefighter will block the view of the
firefighter. As a result, an area must be completely searched until the firefighter is located. If the firefighter is covered by
debris – particularly hot embers – the image of the firefighter may be obscured.
The Pathfinder system uses an ultrasonic Beacon to send a homing signal, which can be sensed by a Tracker. This ultrasonic signal
travels through smoke unobstructed. However, since walls and other surfaces easily reflect ultrasonic signals, a downed firefighter
behind a desk or sofa, or even around a corner, can be easily detected. If a firefighter is covered by debris, the homing signal
will escape through the debris and can be detected by the Tracker. The Pathfinder system is not limited to being a line-of-sight
One of the advantages of the Pathfinder system is that it can tell you not only which direction to go, but more importantly, what
directions not to go. Thus a rescue team can save valuable time by not looking in places where the firefighter is not located.
5. Isn't Pathfinder just like a PASS Device?
No. One of the requirements of a Pathfinder Beacon is that it OPERATES like a PASS device. For the safety of the firefighter,
the unit has to have an automatic means of turning on. It also needs to be activated automatically if the firefighter falls unconcious.
And lastly, there has to be a manual alarm or "Panic Button" for the firefighter to use in an emergency.
The reason the Beacon is not just a PASS device has to do with how the signals are recieved by the firefighter. Think of your ears
and a PASS device as one system and the Pathfinder Tracker and Beacon as another system. The PASS device and Beacon are similar in
that they both transmit sound in all directions (the Beacon transmitting both sound AND ultrasound). The Tracker and your ears are
different, however. While your ears hear in all directions, the Tracker only listens in the direction pointed.
When you try to locate a PASS device with your ears, you hear sound in all directions. When your vision is very limited, or
altogether gone, this can become incredibly confusing. Echoes and non-directional hearing can often lead firefighters in the WRONG
direction, wasting large amounts of time. The Tracker, on the other hand, only listens in a very specific direction. The unit will
tell you the intensity of the signal in the direction pointed. When the largest signal is found, that is the direction of the
SHORTEST path to the firefighter.
6. Does the Pathfinder system interfere with other firefighting equipment?
No. The system does not interfere with PASS devices, thermal imaging cameras, or radios.
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