SlugLife
Contributor
If I regularly found RayBans in dumpsters, I might pick up dumpster diving as well."Dumpster diving" taken literally lol
I'm not willing to bet my life, that in an air-emergency, my swimming-backup-gas will be nearby, alert, available, and have sufficient gas remaining. I always dive with an independent redundant air-source, even when with a buddy.Well, you carry your buddy's back-up gas. But, conversely, your buddy carries your back-up gas. So, a solo diver needs to carry his/her own back-up gas.
I think 3L = 19cu, and 12L=80cu?Yes, I find it somewhat interesting that a 3L pony is often quoted as being insufficient redundancy (600L assuming 200 bar), but a 12L cylinder midpoint during a dive (let's say 100 bar) is considered just fine for two divers (600L per diver)! Of course, all redundant gas planning should be based on likely requirements.
- 19cu: I carry a 19cu on most dives, up to about 90ft/30m. A 19cu would be sufficient (for me) up 120ft/40m, no-deco, and being careful. However, I'd recommend bigger past 90ft (30cu, 40cu, or 80cu) as an additional safety buffer for other issues (entanglements, panic, etc). Personally, I switch to 2 full sized tanks because I dive side-mount and due to wanting more dive-time.
- 13cu & 6cu: I'd love a 13cu for travel, but because I own 6cu (a $35 steal off CraigsList) that's what I usually take. For solo-divers, I'd recommend 19cu+, but these sizes can still (usually) save your life assuming you remain calm, and don't have some other issue (entanglements, panic, extreme depth, lost fin, etc).
- 3cu and smaller: I also own 3cu and 1.7cu spare-airs, and I tested them at 20ft while swimming, and both went "oh ****, I'm empty" in no time. I consider these sizes a hazard, due to a false sense of security, and would consider nothing (no pony) better than ones this small.
- 30cu to 50cu: These are great, but I know plenty of divers who own a 30 or 40cu pony and regulators, who always leave them at home, and "I don't need it this dive" for literally every dive. Borrowing from a concealed-carry saying, "The 13cu on you, is more valuable than the 40cu you left at home." If you're often in the 60ft to 120ft range on most dives, a 40cu probably makes the most sense.
Then there's the "buddy hazard." Ever see an accidents-and-incident's thread where 2 divers die on the same dive? By my estimation, the majority of those involve the first buddy killing themselves, and doing something to heavily influence the other buddy's death.Dive buddies make it difficult to dive with a buddy.