What is the "typical" surface interval for two tank boat dives in Cozumel?

[tracydr]

The PADI eRDP has the ability to plan multilevel dives. It costs about $25 dollars. It doesn't do nitrox but other than that, it could be a good back up and a good exercise to plan your dives. Take the intended depths for each dive site and start planning these dives while you're at home, see what you come up with. Keep plugging in various numbers and try different possibilities to see how different variables will effect the outcomes of multiple dives with multi-levels.
this little gadgets is one of the few PADI gadgets that I actually think is pretty useful and user friendly. The tables are okay but many people have a hard time with them. The electronic RDP is so easy and does the multilevel dives without resorting to the dreaded PADI wheel.
For the amount of time you've been stressing about this surface interval, spending 10 minutes with the eRDP might actually give you some relief and some knowledge of how you need to plan these dives.

 

[Zman96]

Hahah! Well AT LEAST it wasn't AVOCADO GREEN!

That is only after to many margaritas at Wet Wendys.

 

[gasgirl]

The PADI eRDP has the ability to plan multilevel dives. It costs about $25 dollars. It doesn't do nitrox but other than that, it could be a good back up and a good exercise to plan your dives. Take the intended depths for each dive site and start planning these dives while you're at home, see what you come up with. Keep plugging in various numbers and try different possibilities to see how different variables will effect the outcomes of multiple dives with multi-levels.
this little gadgets is one of the few PADI gadgets that I actually think is pretty useful and user friendly. The tables are okay but many people have a hard time with them. The electronic RDP is so easy and does the multilevel dives without resorting to the dreaded PADI wheel.
For the amount of time you've been stressing about this surface interval, spending 10 minutes with the eRDP might actually give you some relief and some knowledge of how you need to plan these dives.

I have a Sim Dive mode on the Suunto computer and it confirmed what Christi said earlier about the Suunto algorithm - NDL really gets conservative for +100 ft depths and doesn"t start crediting NDL back until you ascend to 30-40 ft.

Also, I am not stressing - I am using this as an opportunity to learn about my equipment in all it's capacities.

 

[Basscat]

I dive a Suunto Cobra, but I'm an old fat guy, who didn't take up diving until recently. I'm finally getting to the point on making my air last a while, where the Suunto is a problem. I dive 100 tanks to keep up with the rest of the group, and will get 100 nitrox on future trips for the 2nd dive to make the computer happy and keep me safer. Never quite understand why it's free in Bonaire, and $10 a tank in Coz, but it's a small price to pay in the grand scheme of things. Enjoy your trip, dive your computer, you'll be fine, even if you have to clear a little longer stop.

 

[deborahdelamar]

Hi, again, gasgirl. IMO, you shouldn't worry about the Suunto penalizing you. Most of Coz's sites are wonderful above 80', and if you dive conservatively, you'll have as much bottom time as everyone else.

I use a Suunto Gekko -- the only computer I've owned that never gave crazy readings or conked out during a dive.

Just got back from a REEF survey trip to Isla Mujeres, where most of the dive sites are square profile. Everyone in our group is very experienced. Bottom times of 70-90 minutes on AL80s are common. We use a wide variety of dive computers. We extend our SI's well beyond 60 minutes. But repetitive diving adds up, no matter which computer or algorithm a diver chooses.

On the 2nd tank, next to the last day of the trip, my computer allowed only 4 minutes to the NDL after 51 minutes on an average 47' dive. I had just found a fantastic spot and wanted to record what was happening there. I was disappointed to end this way and grumbled at my Suunto. Because viz in Mujeres is not as wonderful as in Cozumel, I didn't see any divers close by when I started my ascent. When I reached 25', I saw that I was not alone! Almost everyone in the group was above me. So it's a good thing that I have this Suunto that I trust to work. And that I listen to what it says when it says it!

Happy Suunto diving to you!

 

[gasgirl]

Hi, again, gasgirl. IMO, you shouldn't worry about the Suunto penalizing you. Most of Coz's sites are wonderful above 80', and if you dive conservatively, you'll have as much bottom time as everyone else.

I use a Suunto Gekko -- the only computer I've owned that never gave crazy readings or conked out during a dive.

Just got back from a REEF survey trip to Isla Mujeres, where most of the dive sites are square profile. Everyone in our group is very experienced. Bottom times of 70-90 minutes on AL80s are common. We use a wide variety of dive computers. We extend our SI's well beyond 60 minutes. But repetitive diving adds up, no matter which computer or algorithm a diver chooses.

On the 2nd tank, next to the last day of the trip, my computer allowed only 4 minutes to the NDL after 51 minutes on an average 47' dive. I had just found a fantastic spot and wanted to record what was happening there. I was disappointed to end this way and grumbled at my Suunto. Because viz in Mujeres is not as wonderful as in Cozumel, I didn't see any divers close by when I started my ascent. When I reached 25', I saw that I was not alone! Almost everyone in the group was above me. So it's a good thing that I have this Suunto that I trust to work. And that I listen to what it says when it says it!

Happy Suunto diving to you!

Hi, ddeborahdelamar,

We do plan to dive conservatively, but I think most of our 1st dives will exceed that 80 ft depth - but no worries... we have got ourselves sorted on our dive plan.

I would have loved to organize a whalesharks excursion to Isla Mujeres during this trip - I read some awesome trip reports but in the end but it just seemed like it would be too rushed.

I guess it just means we will definitely be planning another trip to come back during next whaleshark season!!

I really have appreciated hearing from all the other Suunto divers about their dive profiles in Cozumel - as someone has already pointed out earlier - I do like numbers!

And it's also nice to have some positive comments about Suuntos to counterbalance all the anti-Suunto sentiment too! :biggrin:

Anyhow, I was talking to a friend from the UK today and mentioned how all the ex-pats I had met in my past trips to Grand Cayman were all such excellent divers.

As it turns out, the British Diving Safety Group which represents all recognised UK training agencies and exists to try to improve diver safety had a nice .pdf on "Advice to Divers Chartering Dive Boats" posted on their website.

Here is an excerpt from that document:

"What about the dive plan? Here there will be quite a big difference between booking onto a dive boat on a space available basis and booking a whole boat for a club or party. If you have booked a couple of spaces, then you will be committed to the dive site the boat has planned for the day you have booked. It is therefore essential that you have checked that the depth and any other factors are appropriate to your own qualifications, currency, experience and fitness. If you have booked the whole boat, you will have more flexibility and you can expect to agree with the skipper a dive site that is suitable for your party.

You must therefore know the limitations of all the members of your party to make this selection. In any case you will be responsible for your own or your partys dive plan for the particular dive site..."

There also seems to be loads of other interesting topics pertaining to safety issues of all sorts - equipment, checklists, accident management procedures, flying recommendations, etc.

Here is the link for any of those readers that might want to check it out : http://www.bdsg.org/

Although it has most certainly been beneficial to me to have posted my questions in the SB forums, it is curious that quite a few readers on this thread felt I was over-analyzing.

Personally, I presume it stemmed more from the earlier posts where there was much angst over what my "actual" concerns were than from me trying to consolidate my dive plan.

I will probably think hard before starting another thread on Scubaboard though... :sarcasm:

Dive Safe and Dive Often!

 

[deborahdelamar]

Off topic: If you want to do whale sharks, get in touch. I took the phone# of person with nice, big, easy on/easy off boat (you need to be quiet getting into the water) who provides great service: Whale sharks, lunch (ok, the sandwich was bad but edible), followed by snorkeling at lovely Ixlache off Isla Contoy, ceviche (excellent), back to Mujeres. Best way is to dive Coz in the am, have lunch, travel to Mujeres & spend the night for an early start. Plenty of time to return to Coz after the trip or to rest & spend another night on Mujeres. Great, inexpensive breakfast at the mercado municipal, local #3. That place also has the best, lightest burritos (vegetarian, fish, and more -- lunch until 5pm) that I've ever had and they don't understand portion control -- servings are HUGE!

 

[Ron Lee]

gasgirl, I dive with a Suunto Mosquito (wrist mount) and a Cobra. I do not ever recall surfacing earlier than the group excepy this past April when I went up to stay with a novice diver who surfaced early. I do not let novice divers stay alone (see my signature which in part was brought about by the female diver who was lost earlier this year).

However, I do sometimes have to ascend early on deepish second dives (50-70 feet) where the terrain is basically flat and there is no reef structure at shallower depths. I notify the DM that I am going up a but and leveling off. I face into the current and SLOWLY swim and almost always stay above the group and surface together. I may have to be shallower than 30 feet but no worries.

Nitrox may reduce or eliminate this situation. I just can't give concrete recollections since I am new to nitrox and do not always use it on the second dive. I have made a second dive with one computer set to nitrox 21 (air) and the other nitrox 32. It can make a significant difference.

Since you have shown that you know of possible hazards and are learning how to cope with them (good on ya), I would suggest that you hire a private DM for your first day. Discuss with the DMs and boat captain as required what you will do. Learn about getting behind coral heads if you get ahead of the group.

Plan on simulating a downcurrent on the first dive. Discuss in detail how you may respond and how the DM will simulate the event. It need not be a surprise. Just as a possible scenario....you have discussed on the surface exactly how the simulated downcurrent will be done. The DM notifies you when it will start and he starts the simulation...perhaps it is slowly pulling you down. You simulate adding air to your BC and obviously that does not help. You are still slowly descending. If your plan is to swim along the wall in the direction of the prevailing current to escape the downcurrent, do that. When the DM judges that you have safely cleared to localized event, you stabilize and continue the dive.

On both dives you can ascend and surface separated a bit from the rest of the group to simulate how you would safely surface if you get separated. Details to be discussed with the DMs and boat captain.

On the second dive, if regardless of the site, about ten minutes before the group surfaces, pretend that your computer is about to go into deco and ascend with your private DM to some depth shallower than 30 feet and practice staying above the group. Again surface slightly separated to simulate being alone or with your buddy.

I suggest reviewing what your computer looks like in deco mode so you are not surprised. While I cannot suggest that you let it go into deco mode, it would be a very useful scenario while with a private DM so you can see how it responds. Mine have cleared by about 60 feet on deeper dives.

I am impressed with your apparent desire to evaluate dive conditions at a new location and learn to deal with them. Your Suunto need not be an issue and where it is (like a deep second dive), you will be able to deal with it. The deep second dive is one reason that I do not like Santa Rosa for a second dive.

Enjoy Cozumel.

As an aside, on dives where reef goes close to the surface, I am often 10-20 feet above the group for most of the dive (after the initial 10-15 minutes).

 

[yaml]

i dive exclusively with jeremy at Living Underwater; with boat trip to and from beach resort (playa palancar), great lunch, gearing up and predive review, the surface interval is always over 2 hours; and jeremy requires all divers to be on computer; even with that my wife and i are typically dropped off at our pier between 1 and 1:30; great DM and crew, great dives, great SIT = LOTS OF SAFE FUN; wouldn't do it any other way

 

[Ray and Pam]

We bought the Suunto because they are conservative, we started diving about 5 years ago and are in our early 50's. Pam has the "Geek o" and I have the Vyper. The first couple years we dove Bonaire and local lakes, shallow stuff and basically used our computers for recording depth and time in our log books. On our first trip to Coz when we got to our safety stop our computers said we had to do like a 7 minute safety stop. Now we know to check our computers for how much time before we go into decompression diving. We were in Coz this May and alot of our 1st dives began at about 100'. Although as the dive continued we were slowly getting shallower due to the landscape but still towards the end of the dive we would have to come up to about 30 or 40'. After a couple days we realized just don't go down to 100' if thats where the bottom was, stay a little higher and let the landscape come to us. Probably shouldn't bring it up but it seems like more people are getting bent now that computers are being used rather than using tables.