Trimix: what's going wrong?

here are more and more incidents reported involving divers using mixed gases at depths greater than 50m. Richard Stevenson poses some tough questions for technical divers and provides some frank and provocative answers

Richard Stevenson
A 29-year-old mixed gas, rebreather and cave diving instructor. He is also an instructor trainer for the training agencies IANTD and TDI. He runs Deep Blue Diving based in Cheshire and regularly organises expeditions to places such as the French caves.

The last two years have seen a rise in the number of technical diving accidents and fatalities, according to the incident reports compiled by the BSAC. Should we sit back, shrug our shoulders and pass it off as, 'Only natural - more divers, more accidents', or do we take steps to try to locate the source of the problem?

Many reasons have been kicked around for the increase in incidents, including the introduction of recreational closed-circuit rebreathers, but I believe the answer is very simple. The increased demand for agencies and instructors to train more and more technical divers has led to shorter, cheaper courses being run for relatively inexperienced divers. The inevitable result has been a drop in training standards and the emergence of a new breed of tekkies who simply are not adequately prepared to make deep mixed gas.

So how do we start to sort this problem out? To be honest, it really falls at the feet of people such as myself. As instructors we are responsible for making an accurate evaluation of a diver's skills in a very short time - but is it enough time? If I had my way, every training programme would take at least a week to complete, giving plenty of time to learn and master new skills and consolidate old ones. But I forget the ever-nagging refrains of 'We must keep the costs down for the sake of the students' and 'We can't expect anyone to take a week's holiday to take a diving course'.

Why has there been a dramatic rise in technical diving accidents?
1 There are more technical divers
2 Training is poor
3 Too many dive beyond their skill


Why not? You may think that's an unfair comment, but when you've had a student ask why a closed-circuit rebreather course had to be five days when it could probably done in three, you begin to wonder what goes on in some people's heads. Three days to gain competence using a life support system that's totally different to anything you've ever used before ... I wouldn't want to do it!

But it's not just students wanting short cuts. The amount of inadequate instructor training that goes on, and the lack of individual skills in some technical instructors continues to amaze me. Perhaps the students who believe that courses cost too much do have an argument? Let's face it. there's not much you can learn from someone who has only made a handful of technical dives themselves. And yet, there are Trimix instructors out there who 12 months ago had never even used the stuff. I know of at least three divers who have recently made such a graduation into teaching mixed gases; one of them had to be rescued by a student he was teaching.

Don't get me wrong, there are a lot of conscientious deep divers out there. In fact, until several years ago I would have said that amateur British Trimix divers were the best in the world. The main reason for this was their healthy attitude to the sport, built up over many years' experience. We know that diving Trimix is much safer than air on deep dives, so we should use it. But doing so doesn't make us invincible. It's important to build mixed-gas experience at a slow rate, gradually increasing planned maximum depths. If you've only ever dived to 50m on air, it's dangerous to immediately begin planning 80m dives on Trimix. At this depth, every move you make has to come naturally. You can't afford to have to think before taking action if a problem occurs. Bolting for the surface is even less of an option.This is why we've had so many accidents - inexperienced divers have a minor problem and freak out. The thing is, if nobody tells you you're not ready to make these sort of dives, how can you be expected to know until it's too late?

So come on instructors, have a bit of pride and think about what your job is. Don't rush into teaching something you're not ready for, and if you have a ticket, think about the divers who come to you for instruction. If you want to be rich, get another job. Some of the best deep dives are right on our doorstep, but let's not kill ourselves getting there. Blame can be apportioned at every level of technical diving, including the training agencies, so let's pull together and address the rise in popularity of the sport properly.

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