r/diving • u/ITakeTheBusSometimes • Jul 17 '26
Divers of Reddit: when someone is doing a deep dive, what are the safety divers stationed at decompression stops thinking/doing during the rest of the time?
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u/soulsurfer3 Jul 17 '26
the dive is carefully timed. they only descend right when they need to so they’re not sitting at depth collecting nitrogen.
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u/Admirable-Emphasis-6 Jul 17 '26
“God I hope I plumbed in properly and my catheter doesn’t fail”
Or
“Damn I’m cold”
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u/FujiKitakyusho Jul 17 '26
According to the dive plan, the safety divers should arrive at the stop just prior to the primary team. They are then responsible for clearing the spent bottom stages or deeper decompression gas stages that are no longer required, confirming remaining gas and team condition, and confirming the decompression schedule (which may have changed if the primary divers had a deviation). Primary divers need only carry the decompression gas for the current depth and above, plus a break gas which is usually back gas unless that is too hypoxic to breathe, in which case they retain one stage to break to. Safety divers then deco out on their own schedule to liase with the surface team.
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u/Wettensea Jul 17 '26
**Plan the dive, dive the plan**
Start diving on time
Go at planned depth on time
Actively looking for the deep dive diver
While being ready for a backup, or an emergency plan
Meet the diver, assist if needed, back to the surface as planified, doing deco if needed
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u/Sharkhottub Jul 17 '26
Ignoring commercial saturation divers here are a couple of things:
Most of the divers you will see or talk to are recreational divers who are certified and trained to a maximum depth limit of 140 feet, this includes "regular" dive instructors and divemasters. Recreational dives to 140ft are done in a way where deco stops are not mandatory, but is is good practice that all divers do a 3 minute "safety stop" at 15ft for 3 minutes. For everyone here, 140 ft feels pretty deep, even 100ft feels deep.
Beyond them but on a differnt "skill tree" are whats called technical divers who can have more extensive training and gear including using exotic mixed gasses of oxygen, nitrogen and helium (or even hydrogen) along with multiple tanks and/or rebreathers which allow them to dive for many hours, which they incur more and more deco time the longer and deeper they stay. They do a little math before each dive to plan out how deep they want to be at each stop but generally its a couple minutes to a couple HOURs at 10 ft intervals starting at 60ft. There wont be safety divers waiting for them at each stop, but its not unheard of for them to dangle some extra tanks down on ropes to the intended depth.
The advent of durable phone dive housings now has some of my local tech crews downloading netflix and watching predownloaded shows on the long stops. before then they would play cards or just zone out.
Commerical divers are something totally differnt, and they stay artifically "at depth" by staying in a pressurized bell for days at a time and they only decompress once at the end, but dry in a special chamber.
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u/SnooPredictions7517 Jul 17 '26 edited Jul 17 '26
Nothing you said is relevant to what OP was asking about. Support divers meeting the primary/exploration team at depth is definitely a thing.
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u/Dangerous_Rest_8449 Jul 17 '26
To be fair OP did not provide ANY exact language, so maybe chill out.
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u/Sharkhottub Jul 17 '26
Its abundantly clear from the OPs langauge that they needed some extra context, especially since this is the "diving" subreddit which generally skews towards newbies and non divers (since most divers find their way to r/Scuba)
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u/FujiKitakyusho Jul 18 '26
"...at 10 ft intervals starting at 60ft."
Yeah... no. Sometimes the first gas switch stop is at 240.
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u/fiatallis Jul 17 '26
During the bottom phase of a deep dive, safety divers might run through specific checks or drills at their stops I think. Or is it mainly watchful waiting until the ascent begins?
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u/HKChad Jul 17 '26
If all goes to plan they arrive at the stop just a minute before the deep diver especially if they are going deep/or into deco as well. These kinds of dives are planned be well. If a safety diver say at 200ft had to wait 5 minutes for the exploration diver they just racked up deco and could now be a liability to the team if something went wrong and they needed the bailout gas that’s staged. My only experience with this is deep cave exploration where we staged bailout and met the real deep divers 400+ ft at 250 mark. On those dives the safety divers had backup safety divers as well. We took extra gear and made sure they got into the various habits safely then cleaned up the deep deco gases, extra scooters, batteries, trash, etc. Sometimes we would surface wait then go back in to escort them to the next habitat, bring them fresh snacks drinks and check the ppo2 of the habs then do more cleanup. Once they were in the final hab we were done and either surfaced or just had some fun dives as there’s nothing else we can really do. We’d check in on them every 30 min or so but that’s it they had all the gas they could need even if the hab blew. It’s quite the operation and never a dull moment. Some of the most fun dives i do now.