The buddy check is a procedure carried out by scuba divers using the buddy system where each diver checks that the other's diving equipment is configured and functioning correctly just before the start of the dive. A study of pre-dive equipment checks done by individual divers showed that divers often fail to recognize common equipment faults. By checking each other's equipment as well as their own, it is thought to be more likely that these faults will be identified prior to the start of the dive.
The wide variety of types of buoyancy compensator, diving suits and types of scuba equipment means that it is important for each buddy to understand the other's equipment configuration in the event that one has to help or rescue the other. The buddy check is a last minute opportunity to become familiar with the dive buddy's equipment.
Similar systems are used by technical team divers and professional divers with the similar goal of ensuring that the divers are ready to safely enter the water. Professional divers may be required by organizational policy to use an itemised checklist.
The basic buddy check is a pre-dive equipment check intended to reduce the risk of the diver entering the water with life-support equipment which has not been checked to be functioning correctly. The extended buddy checks include dive planning information sharing to improve the ability of the divers to co-operate usefully both during the planned dive and in case of a contingency, and may include a review of the current conditions and a basic risk assessment. Checklists have been shown to be highly effective at reducing operator error in several fields where the correct completion of a series of tasks is of critical importance. Although generally not a written checklist, a simple buddy check can be effective in avoiding major problems due to failure to prepare critical equipment correctly.
There are several formats of buddy check, but almost all cover these four aspects:
- Checks on breathing apparatus function and breathing gas supply.
- Checks on buoyancy and weighting equipment.
- Checks on harness security and connectors, and quick release functions.
- Checks on hose routing, attachment and presence of auxiliary equipment: Mask, dive computer, knife etc.
Buddy checks may be extended to include aspects of dive planning, to ensure that the divers are agreed on the intended activity and contingency plans. When larger groups and more complex dive plans are involved this would be considered part of the dive briefing.
- Risk assessment update
- Emergency plans
- Contingency plans
- Dive plan, including planned activities, route, decompression if applicable, and who will lead.
Breathing apparatus checks
- Adequate supply of breathing gases. (cylinder volume and pressure checks)
- Suitable type and quality of breathing gas. (correctly and unambiguously identified if applicable)
- Cylinders mounted securely and accessibly.
- Valves opened or closed as planned, accessible if applicable.
- Demand valves functioning correctly. (work of breathing low, no leaks or free-flows)
- Hose routing correct, no kinks or hoses trapped under other equipment, pressure gauges accessible.
- Demand valves secured correctly where applicable.
For rebreathers the list is longer and may include:
- Oxygen monitoring functioning if applicable.
- Prebreathing has been done to ensure scrubber function.
Buoyancy and weighting equipment checks
- Low pressure inflation hose secure and free of leaks.
- Operation of inflation and deflation valves to ensure that BCD can be filled and vented.
- Oral inflation valve function.
- Dump valves function and accessible.
- Weight belts or weight pockets in place and have the correct weight to compensate for the diving suit and other equipment.
- Trim weights secured if applicable.
- Dry suit inflation hose connected if applicable, inflation valve functions without sticking.
Harness security and release function checks
- Scuba/BCD harness adjusted and secured, buckles accessible for quick release as applicable. Straps adjusted and lying flat.
- Weight belt secured, buckle accessible. Belt free to drop clear if ditched in an emergency. Integrated weight system pockets secure, accessible and free to ditch in an emergency.
- Other equipment attached to the diver secure, accessible and can be removed if necessary.
Presence and condition of required equipment
- Diving suit fasteners done up correctly, Dry suit zipper closed, neck and wrist seals lying smooth and good fit.
- Mask (and snorkel if applicable)
- Depth gauge and timer or dive computer. Computer set to correct gas if applicable.
- Diver's knife or cutting implement secure and accessible.
- Compass, slate, cameras etc. secure.
There are several mnemonics for the buddy check taught by the various training agencies.
- B - BCD
- Check function of BCD. Operate inflation and deflation valves to ensure that BCD can accept and release air. Test oral inflator. Operate all dumps to check that air can be dumped quickly. Ensure straps (shoulder straps, cummerbund) have no slack, and are lying flat.
- W - Weights
- If a weight belt is worn, check that the belt is secure, and the strap arranged so that it can be released with the right hand of the diver. Ensure that weights on the belt are not likely to shift during movement, and are suitable for the diver. If a weight harness is worn, or the BCD possesses an integrated-weights system, test system for adequate operation. A secondary aim is to ensure that the buddy is familiar with the weight system of the diver being checked, and is able to operate them in an emergency
- R - Releases
- Locate and check that all of your buddy's releases are properly secured and you know how to undo them in an emergency. This includes their Velcro waist band and at least two shoulder clips. Many BCDs also have a chest and stomach clip. It's a good idea to touch each clip as you check it and even count each one out loud as you do so. Remember to check the tank strap and clip. You can do this by placing one hand on the bottom of the tank and the other on the first stage regulator and trying to move the tank up and down to see if the strap moves.
- A - Air
- Fully open cylinder valve. The practice of closing by a quarter-turn is recommended by some instructors as it leaves the valve easy to turn, which allows a quick check to ensure it is not closed. A fully open valve may be damaged if the cylinder is empty and someone tries to open it, thinking it is tightly closed, as may happen if the cylinder is empty. However, this practice has been widely discouraged, after several fatalities, including that of famous cave diver Sheck Exley, were attributed to divers mistakenly closing the valve and then opening a quarter turn. (This means that adequate airflow may be delivered at the surface, but restricted at depth due to increased air density.) Breathe the air through the regulators to ensure that it is fresh and dry: impure air is extremely dangerous underwater, but can usually be recognized through an unpleasant, often oily, taste or smell. Test operation of primary and secondary regulators. Both should breathe comfortably, and not 'free-flow' when purged. Make sure you check SPG when test breathing through regulators when breathing the air pressure gauge should not drop. Check hoses for damage. Ensure that the secondary regulator (the 'octopus') is attached in the triangle between the chin and the base of the ribs, and can be released easily: this ensures easy access for a buddy in the event of an emergency.
- F - Final Check
- Conduct a final check of the diver. Ensure that hoses are clipped to the diver neatly, and are in the correct configuration. Make sure the diver has fins and a mask, and any other accessories (cameras, reels, knife, compass, torch etc.) needed for the dive. Check that these are secured to the diver, or else placed in a spot where they can be handed down once the diver is in the water. Correct anything else that needs doing.
PADI teach the mnemonic Begin With Review And Friend, but many divers have their own.
- B - Buoyancy
- Test and demonstrate how each buoyancy device, such as a buoyancy compensator or dry suit is inflated or vented. It is important to test common failure modes, for example, that the device remains inflated when required and that the inflation stops when required. Rebreather divers may test the breathing loop to ensure that it does not leak under a positive internal pressure and negative internal pressure.
- A - Air
- Test that each air source has its pillar valve open, has sufficient gas, is functioning and tastes good. If the indicating needle of the contents gauge vibrates when the diver inhales that may indicate the diving cylinder pillar valve is only partially open and will not provide enough gas at the higher ambient pressures at depth. An oily taste to the gas may indicate a contaminated gas fill. Some rebreather divers breathe from the loop for 2 or 3 minutes before entering the water, to check that the soda lime of the carbon dioxide scrubber is active.
- R - Releases
- Demonstrate how to operate the releases that can be used in an emergency to separate the diver from the weighting system, buoyancy compensator and SCUBA unit.
- S - Site
- Is the chosen site diveable under the prevailing weather and tidal conditions? Are currents, riptides, or other hazards present?
- E - Emergency
- What are the established emergency procedures? Is emergency oxygen available? Where is the closest recompression chamber?
- A - Activities
- What is the purpose of the dive? Are there any special risks or concerns that must be addressed?
- B - Buoyancy
- Check negative and positive buoyancy control devices (this includes environmental suits and equipment); know where your buddy's weights are in case you have to drop them.
- A - Air
- Both buddies check each other's first and second stages, confirm the locations of their octopuses, and proof check by breathing from each other's equipment. Know Surface Air Consumption (SAC) rates and how much air you and your buddy have before you get wet.
- G - Gear
- check your (other) gear. Then go.
DIR equipment check
- place and form attachment
of each item of their standardized diving equipment. This is a part of the check.
The complete dive plan review is: SADDDD
- Sequence: Who leads, who follows, what are the responsibilities of the team?
- Air: Turn pressure, actual decompression ('deco'), bailout deco.
- Distance: penetration of a cave/ wreck, how far from boat/ shore, etc.
- Depth: max and average depth of the dive.
In 2006, SADDDD was replaced within the Global Underwater Explorers organisation with GUE EDGE which stands for:
- G : Goal, dive objectives
- U : Unified team, team strategies
- E : Equipment match
- E : Exposure, depth/time
- D : Decompression strategies
- G : Gas strategies
- E : Environmental issues
- Sport Diving, p118,123, British Sub Aqua Club ISBN 0-09-163831-3
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- Ranapurwala, Shabbar I. (Winter 2013). "Checklists: Keys to safer diving?". Alert Diver Online. Divers Alert Network. Retrieved 27 December 2016.
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- Global Underwater Explorers (2006-11-06). "GUE Procedural Changes" (PDF). Retrieved 2009-03-18.