The OP wanted to go from ER to Advanced mix with no normoxic class. Presumably there would be normoxic dives as part of a class that is going from air at 180 to hypoxic mix. And you said it was "allowed" so I asked what the class would look like.
If its not progressing continuously from ER through normoxic to hypoxic then what is it?
Ok, I understand what you're saying.
Normoxic isn't a mandatory prereq for hypoxic. Either normoxic or extended range is. So a person going from TDI Extended Range (a 180' cert) or IANTD Technical Diver to hypoxic doesn't need to take a normoxic class as part of a full mix program, they've met the pre req as far as certification is concerned.
If you want to debate the merits of requiring someone that's got a reasonable amount of experience doing 180' dives on air to take a normoxic class before they can enroll in a full mix class, I'm all ears.
In regards to what a full mix program looks like, there's a difference in the standards for minimum dive requirements and depth progression in open circuit and closed circuit full mix, but generally speaking a person doing full mix is looking at a minimum of 5 days, and more likely a full week. Generally speaking progression would likely look something like:
Dive 1 - shallow <80' skills and evaluation dive.
Dive 2 - 130-150' trimix dive
Dive 3 - 160-180' trimix dive
Dive 4 - 190-210' trimix dive
Dive 5 - 220-240' trimix dive
Dive 6 - > 240'
Dive 7 - > 240'.
That progression would involve keeping depth increases to 30' between a set of dives, slowly building up the depths, to a max depth below 240'. Dives 1/2 and 3/4 could potentially be on the same day, personally, once we're jumping below 200' I prefer to keep it to one a day.
