In general but especially in scuba we want things to be simple so you can rely on yourself in case of emergency.
Personally I am keeping these rules
Rule number 1
Stay within limits. If medical care is going to be delayed then a more conservative limit must be maintained
Rule number 2
If medical care proximity is over 1hr then O2 (100% if possible) must be available on site. (not in the dive center etc)
Rule number 3
Insurance. The only insurance company that operates in Greece and will allow you to speek to someone in your own language (or at least in English) is DAN. DAN emergency repsonse in Greece is made from the Navy Hospital and will advise and/or arrange evacuation to the appropriate/nearest deco-chamber facility
Finally when diving outside my home town without a dive center, I always keep an eye of where should I go (and how), whom should I call and who is going to alert SAR for me when I don't return on a certain time. Diving on a well known places shares the same though these info were prepared years ago
