Buddy Check Step by Step: BWRAF and the Faults It Catches

What is a buddy check and when do you do it?

BSAC defines it as an equipment check you perform with your buddy immediately before entering the water. Do it last, once both of you are kitted up, so nothing changes between the check and the entry. SSI puts the time needed at under a minute.

It has two jobs. The obvious one is catching faults in gear that has been assembled or put on wrongly. The second is learning how your buddy's equipment works, because in an emergency you may have to find their alternate second stage, inflate their BC or drop their weights without asking. PADI gives this as one of its reasons never to skip the check: with gear you don't know, you respond more slowly or can't help at all.

The skills behind it, and the rest of the entry-level curriculum, are covered in our training guides.

BWRAF, SEA BAG, ABC and BSAC compared

There is no single standard. The DAN researchers behind a 2012 checklist trial note that there is no gold-standard pre-dive checklist and that agency checklists can differ considerably in content. PADI uses BWRAF. NAUI's manual uses SEA BAG, which adds site, emergency and activity planning to the equipment check. DAN lists ABC (air, buoyancy, clips and releases) as another common version. BSAC's Safe Diving Guide describes what its check should contain without an acronym.

Put side by side, the equipment items overlap almost completely. The real differences are whether the dive plan is part of the check and whether the out-of-gas response is rehearsed. If you learned a different acronym, compare its items with the rows below rather than the letters.

B: checking the BC

Press the power inflator, let the BC fill, then vent it through every dump valve, including the overpressure valve. DAN adds the oral inflator. In a dry suit, check that the inflator hose is attached and that the exhaust valve works.

This step catches real faults. In DAN's case files, a group of certified divers on a Hawaiian shore dive found out at waist depth that one BC would not inflate: the inflator elbow on a brand-new jacket had never been screwed onto the BC. Among the first 1,000 reports to Australia's Diving Incident Monitoring Study, the power inflator failed to work in 14 incidents, and the author judged that a careful pre-dive check would have found almost all of them.

Watch the whole cycle, not only the inflate button. When Chris Acott asked 55 divers to check a deliberately faulty rig, 85% spotted the disconnected inflator hose, but only 22% noticed the loose dump valve and 18% the torn oral inflator.

W and R: weights and releases

For weights, find every piece of lead your buddy carries and how each one comes off. PADI suggests a gentle tug on integrated pouches to confirm they are locked in, and a look at belts and rear trim pockets. BSAC wants the emergency weight release covered in every check, because after an incident the weights may have to come off as soon as you reach the surface.

For releases, go over the cylinder band, shoulder straps, chest strap and waist buckle. DAN adds that the cylinder band should be tight. A loose cylinder is easy to miss while you stand on deck and hard to fix in the water: in Acott's test, 40% of divers missed a cylinder that was loose in its harness, and 9 of the 108 unsafe conditions reported by divers in a DAN field study were tanks not well secured.

The same DAN study found that the most common unsafe conditions were being underweighted or overweighted. A buddy check will not tell you whether the amount is right, only whether it is there and releasable. Our guide on how much weight you need covers the in-water check that settles the number.

A: checking the air

Open the valve all the way, then breathe from both second stages while watching the pressure gauge. The needle should stay still. If it dips on each inhalation and recovers, the valve is only partly open. DAN suggests exhaling into a regulator before the first inhalation to clear anything inside it. PADI puts it bluntly: a quick breath or two off the regulator is not enough.

DAN's incident files show why the gauge matters. One diver test-breathed the regulator without looking at the gauge, rolled off the boat and got no air on the first breath underwater; the valve was closed. Another had turned the valve fully off and then half a turn on, instead of the reverse. The needle flickered with each breath, and at 17 m (55 ft) breathing became hard with about 83 bar (1,200 psi) still in the cylinder. DAN calls this an error reported every year and says a valve should be either fully open or fully closed.

Read the pressure too. In Acott's test, 76% of divers noticed the closed valve but only 29% noticed that the cylinder was empty, and the same share noticed tape left over the valve outlet. Gauges themselves fail: contents gauge faults were the largest single group of equipment failures in the Australian incident study, and the author advised comparing your reading with your buddy's before, during and after the dive.

BSAC adds one more item: show your buddy where your alternate second stage is and how to use it, ideally with a dry run of the out-of-gas response.

F: the final check

Do a head-to-toe check of each other. PADI's list is mask, snorkel, fins, light, knife and camera. DAN adds signalling devices and a defogged mask. Two items deserve a second look.

Fins: Acott's review of equipment failures cites a fatality analysis in which 10% of the dead divers were missing one or both fins, and concludes that a pre-dive check must include the fin straps. Dive computers: switch them on and look at the screen. In the Australian incident data, 6 of the 11 computer failures led to harm, and none of those divers had tables as a backup.

The final check is also the natural moment to confirm the plan: maximum depth, turn pressure, signals and what you will do if you lose each other. NAUI's SEA BAG builds that into the check. PADI's safe diving practices ask divers to plan communications and procedures for reuniting before every dive.

• Mask on the forehead or neck, strap and skirt intact, defogged.
• Fins on and straps secure.
• Computer switched on, correct gas set, battery showing.
• SMB or other signalling device where both of you can find it.
• Plan agreed: depth, time, turn pressure, separation procedure.

Why a written checklist beats a memorised acronym

Because the research shows divers remember the letters and forget the checks. In a 2012 cluster-randomised trial run by DAN at four dive locations, 1,043 divers made 2,041 dives. The group given a written pre-dive checklist had 36% fewer major mishaps, 26% fewer minor ones and 32% fewer mishaps overall: about one fewer mishap for every 25 dives.

The trial's control group gave a second result. Only 8% of those 426 divers routinely used a written checklist, 71% used a memorised one and 21% used none. The written-checklist users reported 69% fewer major mishaps after adjustment, while divers using a memorised checklist did no better than divers using none. The authors' explanation: a diver may recall BWRAF as buoyancy, weights, releases, air and final OK and still forget what to do under each heading.

An older test points the same way. In a study published in 1995, 55 divers at a dive equipment exhibition were asked to do their normal pre-dive check on a rig with nine planted faults. Two found all nine and four found none. There was no time limit, and checks took 2-10 minutes, averaging 5.

What to do if you lose your buddy

Stop, look around briefly, then go up. PADI's version is to search for no more than one minute and then ascend safely; if your buddy follows the same procedure, you meet at the surface. BSAC's guide is shorter, at about 30 seconds, with the instruction to keep looking during the ascent. Agree on which one you use before the dive.

Make the ascent a normal one at a controlled rate, with the stop your computer asks for (see our safety stop guide). If you find each other on the way up or at the surface, BSAC advises thinking carefully about your decompression status before going back down, because a second descent will almost certainly increase your risk of decompression illness.

Separation is common, and it matters. Lost buddy contact was the second most frequent major mishap in DAN's 2012 field study, after rapid ascents. The authors add that compliance with the one-minute rule is questionable, partly because surfacing early costs paid dive time. In a UK review presented at DAN's 2010 fatalities workshop, separation occurred in 55 of 140 analysed deaths (39%), almost always after something else had already gone wrong, such as a diver being too heavy or too buoyant, low visibility or an equipment problem. In groups of three or more, the rate rose to 74%. Australian data on 351 deaths of divers breathing compressed gas in 1972-2005 show 65% of victims alone when the accident began and another 17% separated during it. Our article on whether scuba diving is dangerous puts those deaths in context.