Taking TDI Trimix

[stuartv]

It's not addressed because in modern recreational deco diving it doesnt actually exist.

So, it used to exist, but modern diving somehow eliminated it? People that have reported having ICD hits were diving "before", but it wouldn't happen now?

 

[rjack321]

So, it used to exist, but modern diving somehow eliminated it? People that have reported having ICD hits were diving "before", but it wouldn't happen now?

Look at the historic mixes they were using and the switch depths. Unless you are returning to experimental Bill Hamilton tables and doing stuff like Exley did - switching from trimix to air at 300ft there is no plan required.
If you keep your ENDs <130ft (<100ft is better) and gas densities below ~6gm/l per modern practices; IBCD doesn't exist. It sure gets a ton of words written about it on SB. But in reality, no its not an issue.

 

[w3dge]

Look at the historic mixes they were using and the switch depths. Unless you are returning to experimental Bill Hamilton tables and doing stuff like Exley did - switching from trimix to air at 300ft there is no plan required.
If you keep your ENDs <130ft (<100ft is better) and gas densities below ~6gm/l per modern practices; IBCD doesn't exist. It sure gets a ton of words written about it on SB. But in reality, no its not an issue.

So its not an issue if you follow the correct procedures?

A bit like how having enough gas to complete a dive isn't an issue as long as you follow the correct procedures?

 

[stuartv]

Look at the historic mixes they were using and the switch depths. Unless you are returning to experimental Bill Hamilton tables and doing stuff like Exley did - switching from trimix to air at 300ft there is no plan required.
If you keep your ENDs <130ft (<100ft is better) and gas densities below ~6gm/l per modern practices; IBCD doesn't exist. It sure gets a ton of words written about it on SB. But in reality, no its not an issue.

Thank you for the explanation.

 

[rjack321]

So its not an issue if you follow the correct procedures?

A bit like how having enough gas to complete a dive isn't an issue as long as you follow the correct procedures?

Ummmm well nobody does dives with the kinds of switches that <might> cause ICBD nowadays. 1) those kinds of depths are being done on CCR and 2) even those people still doing 100+m on OC, crazy 75+m switches to air fell out of favor decades ago. Ross still has a warning in some of his software, but it seems irrelevant or inaccurate because people switch from something like 18/45 to EAN50 (which can trigger those warnings depending on settings) day after day with no noticeable impacts.

 

[Compressor]

LOL. I didn't have an issue with my gas bill. We dived air on all but my last dive (to 200'). We hit 180' on air, and I got my Extended Range cert, too. I didn't notice any real difference between 180 on air and 200 on 17/40 (we aimed for 18/45, but the final analysis before diving came out 17/40 - not enough difference to bin a dive). My instructor had me do a couple of things at 180 on air, to illustrate what narcosis does, but neither he nor I could recognize any significant impairment of my response times or cognition. I'm sure there was some, but I was happy it wasn't enough to really show.

Anyway, congrats on getting through and all the stuff you learned and refined! Sounds like it was a great class.

Not trying to be negative but isn't that too deep for air? Problem with narcosis is that one may not know they have it.
Congrats on your Trimix certification.

 

[Compressor]

It was a great class, a bit of remedial sidemount training, but fortunately my instructor also dives an Xdeep Stealth Tec (and cave trained by Steve Martin), so my bottle handling skills improved ten fold. To start things off, we added stage bottle removal and replacement (not drops) just to address any lack of skill with diving with 2 stage bottles in sidemount (if anyone says I should have figured that out prior, I won't disagree, but sometimes you run out of time. Fortunately my instructor took the extra time to address that). We added other things like broken mask and replacement, which on first attempt made me attach a small ring to the top zipper of the butt pouch as it took me forever to find it without it. Mind you, I'm in dry gloves. I now have my backup mask and backup light in pouch that's accessible from the top zipper with a small ring so I can do it by feel faster.

People told me the difference in narcosis on the first day of dives would be monumental. It was. The next day was a little more challenging due to current. When swimming on the surface, we were being pushed out, so when we dropped, we went hand over hand until we dropped over the ledge. First dive on 21/35 to 175 we had the largest dogfish that I've ever seen. Normally those things take off when I shine a light on them, but this one was circling us for a bit. Due to the current though, we didn't stay down too long due to increased gas consumption rate. So we slowly ascended at an angle (had to counter the current and we slightly overcompensated, but just drifted back where we started).

Congratulation on your new certification.

 

[wetb4igetinthewater]

Congratulation on your new certification.

Thanks. I’ll be diving this time to time. I don’t plan on taking any more courses for now until (if) I go closed circuit, but will do workshops with various instructors around the world when opportunity presents itself.

 

[Compressor]

Thanks. I’ll be diving this time to time. I don’t plan on taking any more courses for now until (if) I go closed circuit, but will do workshops with various instructors around the world when opportunity presents itself.

Always learning. A great way of doing things. Always a student of diving. Humble. Love it.

 

[stuartv]

Not trying to be negative but isn't that too deep for air? Problem with narcosis is that one may not know they have it.
Congrats on your Trimix certification.

Thanks.

Some people definitely think 180 is too deep for air. Others feel differently. But, the TDI Extended Range is specifically training for diving to a max of 180' on air. I would (will) do it judiciously, but I would also say (almost) never say never - including never say never dive air to 180.