Couldn't find a better diagram than this one:
Floats are generally used for the "light" lines. We used to run ours about 100 feet back. They are used to separate the other lines that are basically under the boat.
Generally, if the outrigger poles are down and the boat is moving slowly they are fishing with gear in the water. However some may only have the stabilizers in the water to quiet the motion down and would probably moving faster than trolling speed, around 2 knots for salmon. Trolling speeds for Albacore can be about 5 to 6 knots with lines straight back near the surface.
Albacore fishing is usually in the fall well off shore.
As mentioned earlier it is basically like having 6 downriggers with 6 lines stacked on each one and separated with the outrigger poles and floats on the back lines.
So, the "float" lines, which will have about a 10 lb ball on the bottom will pull back maybe at a 45 degree angle is your primary concern. If you see a troller and he is going slow (trolling), he is likely fishing, best to give him all the room you can.