Tobermory Dive Operations

[Coldwater_Canuck]

There was no thermocline as of sunday. We hit 80' on Niagara. It was 43 all the way down. The caves is a cool site, but a 2 dive trip to niagara is much more enjoyable.

I think the Caves is one I just want to do once. I'm sure Niagra has a lot better "replay" value, but Caves is one I feel like I just have to see.

On some of the other boats, there is a captain and a divemaster aboard. The divemaster stays on the boat and gives you a briefing before entering the water.

Are you supposed to tip them?

Also, I do not recomend any diving in Toby without some form of redundant air supply. Air sharing is not good enough for these conditions. 2 divers breathing heavily on 1 first stage is working it way too hard.

What do you mean by "these conditions?" The cold? Regulators are made so they can have 2 people breathing off them, and people dive in water in the 40s all the time without having a "pony requirement".

 

[Graeme Tolton]

Yes, caves are a do once. I am just saying that you would have just as much or more fun there with just a snorkel, swimming through... I will never go there with scuba again. Then again, not everyone would be able to freedive through the tunnels.

If you would tip a DM in the caribbean, you would tip a DM/cap here. It's all what you think their services warrant. They are there for you and probably aren't making a whole lot just to be there.

Yes, I do mean the cold, the depths, etc. The fact is, most of the diving related deaths in this area (and most other areas) are related to either OOA situations or non-diving related medical conditions. Not only are you more likely to have a regulator problem at the cold temps, it is more important in cold water to make a slow ascent, because the colder your body temperature is, the more nitrogen uptake you have.

I am not saying that there is any kind of requirement for a pony, I am saying that if you have a redundant air source and have practiced with and are comfortable using it, you are less likely to be another statistic.

BTW, 38f fresh water is not the same as 38f salt water. It is the freezing temperature of the water that makes the biggest difference.

 

[Web Monkey]

What do you mean by "these conditions?" The cold? Regulators are made so they can have 2 people breathing off them, and people dive in water in the 40s all the time without having a "pony requirement".

People have died quite horribly after OOA problems on some of the deeper wrecks in Tobermory.

I own sealed cold water regs (Atomic M1s) but there's absolutely no way I'd be doing any 120'+ freezing cold dives without a fully redundant air source like doubles or a large pony.

Terry

 

[Coldwater_Canuck]

Yes, caves are a do once. I am just saying that you would have just as much or more fun there with just a snorkel, swimming through... I will never go there with scuba again. Then again, not everyone would be able to freedive through the tunnels.

Personally, I wouldn't trust my breath holding ability for that.

If you would tip a DM in the caribbean, you would tip a DM/cap here. It's all what you think their services warrant. They are there for you and probably aren't making a whole lot just to be there.

Well the thing is in the Caribbean they are usually leading the dive and all that. The divemasters I've seen on boats basically are just there to make sure nothing goes wrong. So it's a little different situation.

Yes, I do mean the cold, the depths, etc. The fact is, most of the diving related deaths in this area (and most other areas) are related to either OOA situations or non-diving related medical conditions. Not only are you more likely to have a regulator problem at the cold temps, it is more important in cold water to make a slow ascent, because the colder your body temperature is, the more nitrogen uptake you have.

I am not saying that there is any kind of requirement for a pony, I am saying that if you have a redundant air source and have practiced with and are comfortable using it, you are less likely to be another statistic.

Oh I'm not going to argue the merits of having a pony, and I plan to buy one myself once I return to Seattle. I think I just misinterpreted your original post as basically needing to have one.

But for this dive it will be close to the warmest part of the year, and I doubt I'll be going past around 80 feet or so, so it's probably not the worst possible conditions. But I agree with you overall.

BTW, 38f fresh water is not the same as 38f salt water. It is the freezing temperature of the water that makes the biggest difference.

Okay you lost me, I know salt water doesn't freeze as easily, but I don't see why this makes a difference with how it effects your body or anything else: why would you lose heat faster in the same temperature just because one of the liquids freezes earlier?

 

[Coldwater_Canuck]

People have died quite horribly after OOA problems on some of the deeper wrecks in Tobermory.

I own sealed cold water regs (Atomic M1s) but there's absolutely no way I'd be doing any 120'+ freezing cold dives without a fully redundant air source like doubles or a large pony.

Terry

I'm not sure I'd want to go that deep anywhere without a pony.

 

[bleeb]

BTW, 38f fresh water is not the same as 38f salt water. It is the freezing temperature of the water that makes the biggest difference.

Okay you lost me, I know salt water doesn't freeze as easily, but I don't see why this makes a difference with how it effects your body or anything else: why would you lose heat faster in the same temperature just because one of the liquids freezes earlier?

I'm assuming the comment was specifically about how regulators free-flow more easily in fresh water than salt, especially second stages and non-environmentally sealed first stages freezing from the outside. It's not that heat transfer rates differ between salt and fresh water. It's the fact that it may be the surrounding water getting in there and actually doing the freezing and thereby triggering the free flow.

Seems to me that there was actually a thread a while back where people were describing how they weren't seeing free-flows in cold salt water, but some of the same equipment occasionally had issues in fresh water, even at roughly the same temperatures or even slightly warmer. Tobermory might even have been specifically mentioned. Unfortunately, I couldn't find that thread again.

 

[Coldwater_Canuck]

I'm assuming the comment was specifically about how regulators free-flow more easily in fresh water than salt, especially second stages and non-environmentally sealed first stages freezing from the outside. It's not that heat transfer rates differ between salt and fresh water. It's the fact that it may be the surrounding water getting in there and actually doing the freezing and thereby triggering the free flow.

Seems to me that there was actually a thread a while back where people were describing how they weren't seeing free-flows in cold salt water, but some of the same equipment occasionally had issues in fresh water, even at roughly the same temperatures or even slightly warmer. Tobermory might even have been specifically mentioned. Unfortunately, I couldn't find that thread again.

Ah thanks, that makes more sense.

Looking back, I'm definitely glad I spent a little extra to get a sealed reg. I know that doesn't mean 100% I won't see a freeflow, but definitely better than not.

 

[elan]

Well the thing is in the Caribbean they are usually leading the dive and all that. The divemasters I've seen on boats basically are just there to make sure nothing goes wrong. So it's a little different situation.

I think that it depends what they are actually doing. If they do help you, with your gear, you getting out of the water etc. I think it's a good thing to tip. On one of our charters at Oakville Divers the captain gave us coffee and donuts during SI at no extra charge, I know him for some time and he is always nice and helpful so I always give a tip.

Oh I'm not going to argue the merits of having a pony, and I plan to buy one myself once I return to Seattle. I think I just misinterpreted your original post as basically needing to have one.

But for this dive it will be close to the warmest part of the year, and I doubt I'll be going past around 80 feet or so, so it's probably not the worst possible conditions. But I agree with you overall.

Okay you lost me, I know salt water doesn't freeze as easily, but I don't see why this makes a difference with how it effects your body or anything else: why would you lose heat faster in the same temperature just because one of the liquids freezes earlier?

80 ft is still pretty deep. it's a general attitude here (at least I have seen it) if you go to past 50ft in close to 40F have a redundant air source.

I think what Greame was trying to say about the difference between salt and fresh is that the chances the reg would freeze are greater in the fresh water as the freezing point is higher. Even if your reg is sealed you still have a chance to have it freeze if you get moisture inside. And it can get inside pretty easy. Even if your air in the tank is 100% dry you can still get mist from the air. water from the valve etc. If you get another person on your reg you are cooling it down at least twice as fast so you get more chances to have it freeze.

 

[elan]

Ah thanks, that makes more sense.

Looking back, I'm definitely glad I spent a little extra to get a sealed reg. I know that doesn't mean 100% I won't see a freeflow, but definitely better than not.

You are 100% right. I have seen what could have turned into a free flow it just 3 weeks ago on a second stage od Scuba Pro S600/MK17 It was just inappropriate second stage for that kind of conditions.

 

[Coldwater_Canuck]

I think that it depends what they are actually doing. If they do help you, with your gear, you getting out of the water etc. I think it's a good thing to tip. On one of our charters at Oakville Divers the captain gave us coffee and donuts during SI at no extra charge, I know him for some time and he is always nice and helpful so I always give a tip.

True, I guess I kind of wish I knew what they were making (really this shouldn't be a factor, but it kind of is). Ah all this tipping drives me insane (not paying it, figuring it out, I wish they'd just build it into the price).

80 ft is still pretty deep. it's a general attitude here (at least I have seen it) if you go to past 50ft in close to 40F have a redundant air source.

I guess the question is what do you mean by "general attitude". I certainly don't think it's bad advice, but if it was that commonplace wouldn't it make sense for the dive shops to rent them? And what about OW classes going to 60 feet?

I think what Greame was trying to say about the difference between salt and fresh is that the chances the reg would freeze are greater in the fresh water as the freezing point is higher. Even if your reg is sealed you still have a chance to have it freeze if you get moisture inside. And it can get inside pretty easy. Even if your air in the tank is 100% dry you can still get mist from the air. water from the valve etc. If you get another person on your reg you are cooling it down at least twice as fast so you get more chances to have it freeze.

I looked it up and the difference is about 2 degrees, so if your regulator would freeze in 40 salt water, it would equivalently freeze in 42 fresh water: good thing to keep in mind but not a drastic difference either.

But I'll be extra vigilante in not doing things that are more likely to freeze it (purging, breathing too much at surface, long BCD bursts, etc.). Even though it doesn't sound like I'll hit water below 40, I guess those thermoclines can throw a wrench into the mix (the changes at depth will be the biggest difference for me: in Seattle you can dive any time of the year, basically any recreational depth you want, and you'll always be between 40 and 55. Diving to 100 feet means maybe 5 degrees difference. ) On the plus side the vis should be far better.