The most effective pre-dive Sequence / Check I've actually seen utilized is the one taught by GUE known as GUE-EDGE. If you do not have a regular dive buddy where you can agree on something as comprehensive as the below, you may want to try my "Insta-Buddy Check" instead. The GUE-EDGE pre-dive sequence is FAR superior...but if you are not going to actually use it..then at least do the Insta-Buddy check.
G.oals (objective, specific tasks)
U.nified Team (roles, duties, formation)
E.quipment
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E.xposure (time/depth)
D.ecompression (ascent profile)
G.as (Minimum Gas and Usable Gas Strategies)
E.nvironment
Goals
What are we trying to accomplish. Is this just a get wet dive? Is this a class? Are we wanting to swim around a wreck? Are we wanting to swim around half of the wreck and do a limited penetration of the wheel house? Are we wanting to take pictures?Note the WE statements above. This discussion could certainly start with I want...but needs to eventually land on what we want.
Unified Team
Who's doing what? Who's leading? Assign a "Diver 1" and a "Diver 2" (etc)....Are we going to switch leaders at some point? Who's carrying and launching the primary dSMB? Are we both carrying a dSMB? Am I working the reel and you are supporting or vice-versa? Do we use the same hand-signals, particularly for gas pressure? What is our procedure for a buddy separation? Are you going to be generally on my left or my right? Who's going to manage our ascent and give signals for stopping and moving and watch the clock?Equipment
Generally you want to make this a routine by always starting and ending the same way. So either start at the top of your head and work to your feet. Or start on your right/left side and work across your body. I prefer to start at the top of my head and then work right to left. Assuming a standard recreational dive in a drysuit it would sound something like this (I touch every item as I say it):Starting at top of head...
Diver 1: Mask Ready?
Diver 2: Yup!
Diver 1: Hood On?
Diver 2: Yup!
...We are now going to check everything related to gas...
Diver 1: Tank Valve Open? (actually reach back and make sure it is on - the point of the 'valve drill')
Diver 2: Yup!
Diver 1: Primary? (Breath off of it)
Diver 2: Yup!
Diver 1: Secondary? (Breath off of it)
Diver 2: Yup!
Diver 1: BCD Inflator? (press it twice)
Diver 2: Yup!
Diver 1: BCD Deflator? (press it)
Diver 2: Yup!
Diver 1: BCD Dump valve? (don't actually have to dump with it...just make sure it is screwed in)
Diver 2: Yup!
Diver 1: SPG clipped? (don't remove it...just make sure it's clipped off)
Diver 2: Yup!
Diver 1: Drysuit inflator? (tap it twice)
Diver 2: Yup!
...Switching to right hand...
Diver 1: Computer?
Diver 2: Yup!
Diver 1: Primary Light? (right shoulder Dring - turn it on and then off and stow it)
...If you have a Canister Light you would check the cord as well...
Diver 2: Yup!
Diver 1: Spare Boltsnap?
Diver 2: Yup!
Diver 1: Secondary Light? (left shoulder Dring - turn it on and then off and stow it)
Diver 2: Yup!
Diver 1: Drysuit dump open?
Diver 2: Yup!
Diver 1: Compass?
Diver 2: Yup!
Diver 1: Waist belt? (is it snug and latched?)
Diver 2: Yup!
Diver 1: Right pocket spare mask & wetnotes
Diver 2: Same!
Diver 1: Left pocket DSMB and 150ft spool
Diver 2: Same!
Diver 1: Fins?
Diver 2: Yup!
Diver 1: Deploy Primary (conduct a modified S drill to make sure the hose is not trapped)
Diver 2: Clear!
At this point the last step is doing a "Bubble Check"...and how/when you do it will depend on what your situation is. If you are in the water at say a dock or platform and there is no rush to descend...then do the above pre-dive check in shallow water and end this section with a bubble check. However, if you are on a boat or need to make a negative entry...then call out that we need to bubble check on the descent.
This looks like it would take forever...but once it becomes routine it literally takes like 3 minutes.
Exposure
How deep are we going to go? What water temperature are we expecting? Do we expect a thermocline? Are we suited and booted appropriately for the expected conditions?Decompression
What ascent procedure are we going to follow? Are we going to take a safety stop? At what depth? For how long?There shouldn't be Additional Decompressional Obligations on a recreational dive, however we should at least agree on how we are going to ascend at the end of the dive.
Gas
What type of gas do you have? Is it Nitrox32? What's the MOD on that gas? Does it work for the depth we just mentioned in the Exposure section 30 seconds ago?Unclip your SPG or look at your dive computer
Diver 1: I have 2948 PSI of Nitrox32 in an HP100
Diver 2: I have 3100 PSI of Air in an AL80
Diver 1: Our gas strategy is going to be "All Usable"
Diver 2: Yup!
Diver 1: Our turn pressure is 500 PSI (this should match the depth that was mentioned in the Exposure section 30 seconds ago)
Diver 2: Yup!
Environment
Any boat traffic to worry about? Any dangerous animals? Fire corral? Is the wreck expected to be in poor condition? Is the shore entry sand or rocks? Are there waves or swell? Are we using a downline?Even an aggressive smallmouth bass at the shore entry can mess with your head. Discuss it - plan for it.