Hi, I'm firefighter and dive commander Josh Mueller and welcome to What's on the truck Tuesday. Today we're talking about our dive communication systems. Communication as a diver is critical. It makes us safer underwater and it makes us more effective as rescuers. In the past, we could only communicate with line signals. The diver would communicate using line pulls and the line tender would communicate back using line poles. For example, two pulls on the line would mean change direction if the line tender was talking to the diver. And if the diver was talking to the line tender, two poles would mean give me more line. Let's go ahead and check out the gear. This is our full face mask that we use for diving. It has a microphone built into it. It also has speakers here that sit right up against my ear when I'm underwater. That connects to our comm line. That's 100 ft of communication line that also functions as our tether. And then that connects to the base unit. The line tender will use this on the shore. They'll be able to communicate with two divers and hear everything that's going on underwater. Let's see it in action. Now that we're all geared up, let's go ahead and see how that sounds underwater. Prepare for dive. [Music] All right, now we're at depth and we're going to go ahead and start our search. Copy that. This communication system is fantastic. It gives the diver a lot of security when they're underwater and it also lets me have all the updates that I need as as more information comes in. For safety, it also allows me to tell the line tender how much air I have. [Music] [Applause] what conditions are like down here and what my max depth is. So, as I start my search, I can tell the line tender that I'm starting a search, and when they're ready for me, the line tender will tell me to change direction. Copy that, Josh. Two tugs, change direction. When I found whatever our mission has us searching for, I could tell the line tender exactly what I found. Or I could tell them that I have three tugs. Three tugs. Copy that. I'm at about 20 ft and I got almost no visibility. Oh, gross. All right, I'm coming up. Oh, and if I'm in an emergency, instead of just yanking on the line, I can actually tell the line tender that I'm in an emergency and they can send in my backup diver. Thanks for watching. I hope you learned something new about some of our dive operations.