Procedures, Mnemonics, and Flows

Being a capable diver requires having a fair amount of knowledge, including knowing the procedures to handle whatever situations come up. There are a lot of procedures to learn. Some are used every dive, while others are only used to respond to problems.

To help remember all the procedures, a lot of divers use acronyms and other mnemonics. The most well known one is PADI’s BWRAF mnemonic for predive checks.

I have mixed feelings about these kinds of techniques. There’s no denying that mnemonics are powerful tools for memorizing information – they’re just not that well suited for memorizing diving procedures. My two biggest grievances are that they aren’t adaptable to different situations, and that they take too much effort to unpack under pressure.

First, adaptability: different dives call for different procedures. My predive checks for cave diving, deep wreck diving, and diving on a shallow reef are all slightly different. Most mnemonics, on the other hand, are rigid. They contain a fixed set of steps, and if you want to make any changes, you have to reinvent the whole thing. The BWRAF mnemonic cheats by includes a catchall “F” for “Final checks”, which makes it more general, but doesn’t actually help with remembering the unique checks for a particular dive.

Worse, many mnemonics take a lot of effort to unpack. You have to remember the seed (BWRAF, in this case), remember what each letter or word of the seed stands for, remember what each step means, and then review it all to make sure you didn’t remember anything incorrectly. This might be acceptable for routine procedures like predive checks, but doesn’t work for emergency procedures which have to be done quickly and correctly under pressure.

Instead of using mnemonics to remember procedures, I try to create what I call Flows. Flows are when you take a procedure and “remix” it, removing unnecessary parts and reordering the ones that are left so that each step naturally suggests the next one. If there are any special steps for the dive, a good flow will make them obvious. Usually there’s a theme that ties it all together.

Here’s an example: twinset valve shutdown to stop a gas leak behind my head. (There are a lot of opinions about the best way to handle this situation. This is my flow.) The flow is based on the idea that I need to locate the source of the leak with as little thinking as possible. Losing gas is stressful, so I need to make this easy.

When I hear gas escaping from behind my head, the first step is always to close the isolation manifold. Once I do this, the left and right sides of my twinset are no longer connected, which helps me narrow down the source of the leak. It also means that even if I panic and mess up the rest of the procedure, I only lose half of my gas. Next, I look at my pressure gauge, which is connected to the left tank. If the pressure gauge is dropping, it means the leak is on the left side. Otherwise, the leak is on the right.

Now that I know which side the leak is on, I can close the tank valve on that side. If that stops the leak, problem solved. I can re-open the isolation manifold and turn the dive. If closing the tank valve doesn’t stop the leak, it means the leak is upstream of the tank valve. In this case, since I can’t stop the leak, I breathe from the leaking side to use as much as I can before it’s empty, then switch to the non-leaking side.

With this flow, there are a lot of steps, but you don’t have to memorize them. As long as you can remember to start by closing the isolation manifold, the rest of the steps are a logical progression toward locating the leak.

It’s usually not hard to find a flow for procedures, and it’s worth taking the time to do.

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