I have just started my first of 5 TDI courses and was wonderng what the mandatory dives are for them and the depth/time limits etc :-
Nitrox
Adv Ntrox
Dec and Extended Range
Cavern
Intro to Cave
That sounds like SIX and not five courses (Decompression Procedures and Extended Range are separate courses).
I would suggest contacting your instructor (or training facility) to get current information from them... for example, many TDI instructors will ADD to the minimum number of dives a student must do to earn certification. In addition, when courses ARE conducted in combination with others (advanced nitrox and decompression procedures for example) the number of dives etc. CAN be modified.
A small point but one you need to clarify; a PREREQUISITE for extended range is certification as a decompression diver, therefore the two courses may not be run as a combined course.
However, for the record, here is a listing of dives for the courses you have mentioned.
Nitrox: two recommended but none actually required
Advanced Nitrox: four dives with at least 100 minutes BOTTOM time (not inwater time) with a MAX. depth of 45 metres
Decompression Procedures: four dives with at least 100 minutes of bottom time and two dives to exceed 30 metres.
Extended Range: four dives with at least 100 minutes of bottom time and two dives to exceed 30 metres two to exceed 40 metres.
Cavern: two dives with at least 80 minutes of bottom time and at two different dive sites.
Cave: four dives with at least 100 minutes of bottom time and at two different dive sites.
We do not mandate the duration of ascent times from training dives but the instructor guides for each of the classes that require staged decompression (deco procedures, and extended range) do contain suggestions for the ratio of bottom times to total ascent times. Again, speak with your instructor.
Please send me an email address and I will get you a skills document because you will find this more informative than anything else.