Yep I am aware of the CAA guidlines, along with the PADI, SSI, NAUI, TDI, SDI, IANTD et all (who all have different guidlines!).
Phi, is out in Dubai misbehaving himself as usual. Has found himself a nice shiny 115m sub to dive. Deco weenie is still alive and kicking. A nice presentation of a standard Buhlmann algorithmn.
I agree with you, the old days of slower than the largest bubble always worked for me as well!
Microbubbles are a bit of a misnomer, they will be present in your system after any dive, even a freedive. Where they present themselves problematically is when they seed into larger bubble formations and while theoretically a rapid pressure change from 7k to 30k in the event of an airliner having an incident could present a problem, in realty the pressure changes are measured in fractions of an atm equating to less than a 5m depth change in underwater terms. The cause of seeding is still subject to much argument but flaws in the veins and arteries have been recognised as a source of bubble capture which then causes microbubbles to attract to the site and grow to a size which they then breakaway and head happily off somewhere to do some damage.
Generally speaking if you are going to get bent then it will manifest itself within minutes of getting out of the water, on helium it will actually manifest itself in water. It is very rare for a person to get a "real" bend 24hrs after a dive.
I generally think that anything in the "standard" recreational (a deep dive is classed as anything great than 18m) depth of 0-20m is fine, as long as you are correctly hydrated and are not pre-disposed (PFO etc.). Again it is matter of personal choice, I rarely dive less than 60m these days but am still happy to fly the next day but I understand the decompression methods I use and am so hydrated I could fill a lake.
An interesting diversion from flying talk!
