will soon be doing first saltwater dive

[diversteve]

will soon be doing first saltwater dive

we will be doing a "rig dive" in the Gulf of Mexico

No one else seems to think this is a bad idea? OK, I'll be the bad guy and do the reality check...

I didn't get the impression from my friend - who dives them from his boat in Galveston - that they're particularly easy dives. Isn't there a lot of current and the possibility of live drops/pickups?

Don't be worrying about the sharks Becca. Before you see them, they know you're there. And you're not of interest - too big and all that rubber smells bad. There's also going to be barracuda. They're going to be at least interested in any shiny things you have on. Enough to give you a good looking over - d-rings flash almost like baitfish. So move slowly if you find yourself in that situation - they'll often be hovering in the shadows.

The worst thing likely to happen is you'll bang up against the rig accidentally and get cut up on something sharp - like coral or barnacles. Or hit a sea urchin and spend a few hours pulling spines out later - before they infect. Wearing a shorty on a rusty, sharp, coral filled platform dive seems inherently like a bad idea also...How good do you expect your buoyancy control to be while you're testing weighting configurations?

Just because you see other divers going into tight swim-thru's doesn't mean it's a good idea for you also. Be aware that you two are probably the only couple with no ocean or ocean current experience.

Consider how you're going to get back on the boat if the conditions are dicey. Or change while you're diving - which happens off the rigs in SoCal occasionally. Or if you get blown off the rig or the line. Do you have a safety sausage? Know how to properly deploy it? Comfortable with possibly drifting for a while in open water while other divers re-board? That boat looks pretty small from 200 yds. away.

I don't know that area but standard protocol is that unless a diver is in medical or other distress, the captain won't start the engines with divers in the water. Be sure you ask the dive briefer or other crew member about proper procedures to leave and re-board. Including obvious things like air in your BC. Sometimes you want to float at the surface and get situated, other times it's best to drop and find the line as quick as possible. Sometimes there's a line running from the mooring to the back of the boat. Stay on it, it's there for a reason.

Occasionally it's a live drop - which means the captain gets in close, cuts the engines and geared up divers jump in quickly. Inherent in that is that you typically drop heavy so you get below the surface quickly. To do a live pickup it's pretty much the same. Follow the orders of the captain/crew member about when it's safe to approach the boat - the engines will be running as the captain has to keep it off the rig - just not the props.

And always be very aware of where the ladder is. Especially if you're anywhere near under the boat. And don't crowd another diver going up it - if he falls his tank can smash you in the face.

I hope it works out well for you...

 

[DivemasterDennis]

All of the formulas for weighting are general rules. Useful, but not applicable equally to everyone. Your body type, from extremely lean with very low body fat to extremely obese with a high percentage of fat, will impact the applicability of the charts and weighting. Lean people not only use less weight but the variance is less from fresh to salt. Also, lung capacity , equipment used, and experience and comfort levels all effect weighting. Use a formula as a starting point, but do a weight check near the boat before your first dive in new conditions. You will be glad you did.
DivemasterDennis

 

[CT Sean]

All of the formulas for weighting are general rules. Useful, but not applicable equally to everyone. Your body type, from extremely lean with very low body fat to extremely obese with a high percentage of fat, will impact the applicability of the charts and weighting. Lean people not only use less weight but the variance is less from fresh to salt. Also, lung capacity , equipment used, and experience and comfort levels all effect weighting. Use a formula as a starting point, but do a weight check near the boat before your first dive in new conditions. You will be glad you did.
DivemasterDennis

That is true for "how much weight do i need" type questions, but for the conversion of fresh to salt water, which is the OP's question, it is not. The same rule applies to everything. The total weight of the object (whether it's diver or a box of rocks or a ship) needs to increase or decrease by the same % as the salinity of the water.

 

[Becca65]

Thanks all - very good information. This will not be a "dive boat" with a large group of people - this is a friend's boat with just us and a couple other divers who are both experienced (Gulf) rig divers. Might there be other divers out there at the same time - sure - have no control over that - but our group will be small. The boat will anchor and stay in the same spot while we dive. I hope to not bump into anything - but may decide to wear my full suit just to be on the safe side. And yes, I do know about barracudas and shiny objects and will take care not to have anything I don't absolutely need that even might flash. We will most likely not go deeper than 30' feet or so, if we do need a safety stop we will have the rope off the boat to hang onto while we do that so we don't accidentally ascent too quickly. Oh, and rest assured I will NOT be going through any tight areas - I know I am not ready for that yet.

 

[diver 85]

becca, how far out ya'll heading--& what size boat???......Some people need to consider sea conditions ie wave 'action' on their minds....I've brought some out(that stayed seasick all day---& there's no turning back) that later told me they had a good time but 'never again'.....

 

[DukeAMO]

I always wear a full suit when diving a wreck, because of the chances of getting cut on something if you get surprised by a current or something. The 3mm full suit would definitely be a good idea. I also never touch a wreck with my hands, unless I'm wearing gloves, and even then I'm very careful. So, you should consider light (3mm neoprene or cloth reef) gloves too, or even the stretchy gloves they sell at home depot for plumbing and such: http://www.homedepot.com/p/Grease-Monkey-Large-Gorilla-Grip-Glove-25053-030/202709681

 

[greenliger]

If you see a shark chase it until you get a good pic or vid of it. At least that is what I see everyone do. OK OK I've done it too damn peer pressure.

 

[diversteve]

Hey,

Don't give it away, that's how I get all the good video...I follow anything smaller than me often. Sometimes bigger.

Although once I dropped on a shark - literally. He turned, arched and flashed his teeth then took off. Circled around like he was still mad about it so we got real up close and personal. Then he really did take off. Wish I would've had the camera running before I dropped since I didn't get any of it.

Underneath the boat the captain (inspecting the props) was laughing so hard he flooded his mask.

 

[Becca65]

I appreciate your concerns but I suppose I should clarify - my husband and I own an outboard repair service - this friend's boat is more than capable of making the trip and he regularly goes offshore in it. I'm not sure how far away the rig is, but he's been there many times, we are going this time of the year because at the moment we have very little wind and the water is nice and flat - if something blows in we're still covered because of the experience on board. I think I will take my full suit just to be on the safe side.

 

[MXGratefulDiver]

As I've mentioned in other threads my husband and I got certified last September - since then we've made several trips to dives lakes and a river (and cleaned the bottom of a friend's pool ) In the next few weeks we will be doing a "rig dive" in the Gulf of Mexico - plan to descend on a line - wondering how much weight I should add - is there a standard? I've been told by some friends that they double the weight they use in fresh water when they dive in saltwater.

Somewhere in the vicinity of 4 - 6 lbs is generally sufficient. But if you're doing a rig dive, I'd highly recommend doing a proper weight check in shallow salt water before you go ... rigs are generally dives that don't have a hard bottom, and the very last place you want to be if you're overweighted.

Also - not sure that we'll come across any - but what exactly do you do if you're swimming around and happen to see a shark? Do you continue swimming without any fast movements or turn and go another way or what?

Whatever you do, don't swim away from the shark! People pay seriously good money to go see them ... enjoy the experience.

Movies and media popularize sharks as inherently "dangerous" ... and as large, wild animals they can be. But the fact is that we're not on their menu, and unless we do something to make them feel threatened, they'll generally ignore you. An encounter with a shark is often the high point of a dive ... just respect the animal, and don't do anything dumb like approach it or try to touch it.

... Bob (Grateful Diver)