We all know how important it is to perform a 15-foot deep “safety stop” at the end of a no-decompression dive, particularly if the dive is deep or subsequent dives on a day of multiple dives. But it is important that your safety stop not be sloppy. A sloppy safety stop is when you are tense, bobbing up and down erratically, and breathing heavy. Your safety stop should be steady, comfortable, and not vary in depth more than a couple of feet. There are a number of ways you can do this, but each has its advantages and disadvantages and specific techniques apply to different situations.
A COUPLE OF KEY POINTS FIRST:
A key point no matter how you do your safety stop is neutral buoyancy. You need to be neutrally buoyant at 15 feet with a tank reading 500 p.s.i. You can get a feel for this over the period of several dives. Start slightly on the negative side. You can always add air to your BC to compensate. But in subsequent dives, eliminate unneeded lead a little at a time until just right.
The most important safety stop skill and method is to be able to hang neutrally buoyant mid-water without hanging on to anything and no reference other than the depth reading on your dive computer.
Another important point is to have enough air remaining in your tank to complete the safety stop without the anxiety of running out of air. You need to be able to finish, not start, your safety stop with 500 p.s.i. in your tank. How much you need to have left in your tank when you leave the bottom is dependent on depth and how hard you have to swim.
TECHNIQUES FOR SAFETY STOPS:
ANCHOR OR MOORING LINE
Following the boat’s anchor line down and back up is simple and direct. It will take you straight to, or at least close to, the dive site. With a bit of navigation skills you can go right back and up. It also has the advantage of being able to better pace your ascent rate. But in heavier seas these lines have the bad habit of not sitting still but rather pitching up and down with the waves as the boat above is tossed to and fro. You could find yourself varying in depth as much five to seven feet. Use this technique only when reasonably calm