Is 130 ft too deep?

[Dan Gibson]

Oops. Seems I have been in violation of my PADI certification for quite some time since I don't have a deep diver specialty. Does my DM cert cover me, or am I covered under Cave 2 :06:

Correct:
Padi limits are:
60 ft OW diver
100 ft AOW diver
130 ft Deep Diver Specialty certified

 

[eponym]

Hi all. My husband and I will be diving in Belize and staying on the Lighthouse atoll in December. One of the dives he is really looking forward to is the Blue Hole. It seems to be one of those once in a lifetime type of dives, but I am a bit nervous. I have done about 30 dives with the deepest around 115 ft. I really would hate to miss out on this opportunity (I doubt we will be back to Belize any time soon). But--I promised myself I wouldn't take any significant chances diving (2 kids at home I really need to come back to!). Is this a risky dive?

Pediatron, it's great that you're asking. Shows you're trying to make a good decision before you get there.

You mention 115 as your maximum. Did you plan that depth beforehand? How did it go? What problems did you deal with? How did you feel about it afterwards? Have you made other dives around that depth?

Some might say the blue hole is a once-in-a-lifetime dive. I've not dove it, I can't say. I bareboat chartered in Belize not too long ago and we sailed but didn't dive. I don't regret missing the hole. For that matter, I think my first-ever snorkel (in Cozumel, many years ago) was once-in-a-lifetime great.

Finally, if you do decide to dive it, please re-evaluate that decision with your buddy before you enter the water and before you start your descent. Be sure that it's something you want to do. Some amount of nervousness will be normal, but there should be eagerness too.

I hope some of this may help your thinking.

Best regards,
Bryan

 

[MikeFerrara]

Oops. Seems I have been in violation of my PADI certification for quite some time since I don't have a deep diver specialty. Does my DM cert cover me, or am I covered under Cave 2 :06:

Good question. Though it might have been meant as sarcastic I'm not sure every one knows the answer.

The limits given are the max depths allowed on training dives at those levels and the recommended max depths at those levels until further experience or training is gained.

In the case of a DM, you are qualified to assist in training to 130 even if you've may never been there since a deep specialty is not a requirement to be a DM. Of course the same is true for instructor.

As far as what depth your cave 2 training qualifies you for...I think you are only qualified to go deeper if it's in a cave

 

[Mark Vlahos]

I agree with some of the earlier posts. By simply asking the question you are aware of your limits. This strikes me as a good thing. Training can help get you comfortable with new situations.

December is still far enough in the future that you might be able to get instruction about diving safely at this depth. If you are interested in taking an AOW course it would not hurt you, but you should ask the instructor if he can tailor your instruction to make you a safe and trained diver at the 130 foot level. Don't just take the class; ask for more. It might cost you a little extra but the information can help. Try to find an instructor who teaches "technical" classes. At about 30 dives under your belt you are probably not an ideal candidate for deep diver training but with the right instructor and time you should be able to gain the skills that will assist you in this dive. At 130 feet you will need to pay much closer attention to proper gas management. 500 PSI in your tank at 30 feet is very different form 500 PSI at 130 feet. With an ascent rate of 30 feet per minute at 30 feet you are only one minute from the surface, but at 130 feet you are looking at more than 4 minutes to the surface, and neither of these included a safety stop. Not to mention that at 130 feet you will be breathing down your tank at a much faster rate than if you were shallower, due to the compression of gas at depth.

I would not encourage you to make this dive without additional training and experiience. Even with the training your instructor might not feel you are ready, but only he or she can make that call. Remember your family matters a whole lot more than a dive to 130 feet.

Best of luck,

Mark Vlahos

 

[pediatron]

Thanks for all the advice. We did get AOW certified (but it was on our first dives after certification.) My husband had about 30 more dives than I do and is VERY comfortable with diving. I know he wants to go to 130 ft and I don't want either of us to dive without a buddy if I feel comfortable with less depth. I don't have any problem controlling my depth and I usually have more air at the end than most. I've had a few other dives over 100 ft and didn't have any problems. I will admit though that I have no idea how to tell if I have enough air to get to 130 ft. I would dive my computer and usually am a little more conservative than its recommendations. Does this info help???

 

[Curt Bowen]

Actually the bottom is at 412 feet. There are large bacteria stalagtites at 110-170, very pretty. Not much to see past them except limestone walls and a soft mud/sand mix bottom.

As for diving to 130 feet in the Blue Hole, one must remember its like diving a wall where there is no bottom to stop your descent. It would be very easy to slip down to 140-150 for unexperienced divers.

I would suggest buddying up with the most experienced diver on the trip to watch over you.

 

[Mark Vlahos]

Thanks for all the advice. We did get AOW certified (but it was on our first dives after certification.) My husband had about 30 more dives than I do and is VERY comfortable with diving. I know he wants to go to 130 ft and I don't want either of us to dive without a buddy if I feel comfortable with less depth. I don't have any problem controlling my depth and I usually have more air at the end than most. I've had a few other dives over 100 ft and didn't have any problems. I will admit though that I have no idea how to tell if I have enough air to get to 130 ft. I would dive my computer and usually am a little more conservative than its recommendations. Does this info help???

I think the comment about getting to depth was about gas consumption rates, remember you need a certain amount of gas to get to depth, a certain amount of gas to remain at depth for a given amount of time, and a certain amount of gas to safely ascend to the surface. This is not the total amount of gas required for the dive. You need to add an amount of gas for your own safety margian, you don't want to get to the surface with an empty tank, do you? You also need to factor in enough gas to get to the surface safely with all of the above considerations even if your buddy needs to use your breathing gas at the deepest part of the dive. Remember if your buddy runs out of gas or has an equipment failure at depth your tank might be the only thing you both have to get you to the surface safely, and if this happens you will probably both be breathing at a higher than normal rate. These are some of the scenarios you need to consider as you get deeper. Training can help you to recognize these and other problems early and have plans for what to do if you if the s%!t hits the fan!

Mark Vlahos

 

[sleepyhead]

Thanks for all the advice. We did get AOW certified (but it was on our first dives after certification.) My husband had about 30 more dives than I do and is VERY comfortable with diving. I know he wants to go to 130 ft and I don't want either of us to dive without a buddy if I feel comfortable with less depth. I don't have any problem controlling my depth and I usually have more air at the end than most. I've had a few other dives over 100 ft and didn't have any problems. I will admit though that I have no idea how to tell if I have enough air to get to 130 ft. I would dive my computer and usually am a little more conservative than its recommendations. Does this info help???

You might want to consider doing the deep spec first. It's good to do a few more dives greater than 115 ft to ease you in at greater than 115 ft. You would learn to plan better and estimate your air consumption at that kind of depth. Sometimes, people fail to plan and run out of air.. you don't want to miss a safety stop.. I did a 44 m dive after my deep spec.. as a tech pre sample. You might get narked.
I would definitely agree on going deeper, it's so much fun but keep it safe..
There were 2 Oz divers that died even though they were well trained cuz they run out of air... So have fun and be safe..

 

[Hank49]

Hi all. My husband and I will be diving in Belize and staying on the Lighthouse atoll in December. One of the dives he is really looking forward to is the Blue Hole. It seems to be one of those once in a lifetime type of dives, but I am a bit nervous. I have done about 30 dives with the deepest around 115 ft. I really would hate to miss out on this opportunity (I doubt we will be back to Belize any time soon). But -- I promised myself I wouldn't take any significant chances diving (2 kids at home I really need to come back to!). Is this a risky dive????

Just hover at 110 feet or so just above the divemaster and group. All that's down deepr are the stalagmites and "tites". And as others mentioned, I spent my time looking at the sharks, not the geological part of the dive.

 

[Boogie711]

There is no way I would ever plan a dive to 130 feet on a single AL80, which is what I assume you would be diving.

Think this one through - that's 5 atmospheres. What if you get to 130 feet and your buddy freeflows? You now need enough gas on your back to get you and a slightly panicked buddy through a 130 feet ascent, and pray that you don't have a deco obligation.

Assume one minute at depth to fix the problem, both of you breathing at a SAC of 1cf per minute under stressed conditions - that's 5 cf each, or 10 cf.

Now, one minute to 90 feet, which is slightly faster than you really should be going but it's probably not going to kill you - 4.5 cf each, or 9cf.

One minute to 60 feet is 3.5 cf each, or 7 cf.

One minute to 30 feet is 2.5 cf each, or 5 cf.

Three minutes ascent to the surface (again, this is assuming you don't have a deco obligation) is 3 cf each, or 6cf total.

That's a combined total of 10+9+7+5+6, or 37 cf of gas. On an AL80, that's approximately 1,450 psi that you need to leave in reserve in case of a problem at depth. Considering it may very well take you over 500 psi just to get to depth in the first place, you're not leaving yourself a whole lot of room for actually diving, are you?

Dive within your limits. Blue Hole isn't going anywhere... you can always go back.