Comments on: The Gas Laws and Physics of Diving

By: Cheese Eater!!

Cheese Eater!! — Sat, 30 Apr 2011 03:22:47 +0000

Hi, I’m a high school student from the Gold Coast and my school has decided for a chemistry assignment that we have to research about the uses on Enriched Air Nitrox in scuba diving. And after reading all the comments I was wondering if you could help me with a question. I’d like to know how Nitros compares to compressed air, and which one in your opinion is better.

Thank you :)

By: diverdown

diverdown — Thu, 07 Apr 2011 10:51:11 +0000

Josh,

A good resource for health-related questions is DAN – Diver’s Alert Network. They have doctors on staff specifically trained for diving related questions/issues. They can also suggest a qualified physician in your local community.

Good luck!

By: Ronald

Ronald — Sun, 13 Jun 2010 15:31:58 +0000

To complete that….Nitrox can also mean less the 21% O2….which can/is used on some dives.

By: Lyne

Lyne — Mon, 29 Mar 2010 12:50:19 +0000

Oh god… the stories I can tell about diving. Here are a few pointers that can help make your dive a bit safer and please understand that most of this has happened to either me or an aquaintance of mine.

The first thing to think about BEFORE hitting the water is: is your body and equipment up to specs? Yup, happened to me: Even if you rent your equipment from a dive shop, it CAN be faulty.

I had a leaking buoyancy control device and could hardly control my depth ( my instuctor was also pissed till he reallised it was leaking), my regulator froze open and I had to work at it to keep it closed ( tapping and shaking it, still not fun :( ), If your fins are not fitted right, you can lose them. If you are using a dive computer that is linked to you via an air hose and you compass underwater, make sure the hose is long enough; being off balance and in constant rotation can make you dizzy and it also makes for a dissatisfying experience (This is for the people that have longer arms) . Inspect your tank before each dive: there can be small air leaks around your valve that can cut your time underwater and it didn’t make me feel very safe.

Now, for the Pegasus missile, there is more then one way it can happen, and it did happen to me. Make sure you inspect your weith belt or weight integrated systems. If you hit a sharp object or have a worn weight belt buckle that doesn’t lock properly, you can have a jetpack ride to the surface before you know it. Going spread eagle can maximise your drag, until someone holds your fin to try to keep you under ( hint: it don’t work), then you end up being vertical and going faster. You have a couple of vents on your bcd that helps if you open them, but not much. If you happen to be diving in cold water and have a 7.5 mm wetsuit, you go up faster then if you only have a 0.5 mm for warm water; more insulation equals more buoyancy. The trick to surviving the missile effect is to exhale like the mofo and to not hold your breath at all.

Now these funny lil mishaps all happened to me during my test dives, when I trusted a dive shop for most of my equipment. The weight suit and weight belt were bought second hand. What I normally suggest is that you buy your equiment and keep it serviced on a yearly basis. Also do a thorough inspection each and every time you dive.

Us Canadian divers tend to store our tanks over the winter. Remember to change the air in your stored tanks before going diving again, wouldn’t want to be sick from bad air.

For the body part: Even having a flu can ruin a dive. Know the effect of the meds you are taking in an underwater environment ( also applicable to asthma puffers and every other ailments you would take meds for) . I almost had ear barotrauma after I got air locked in the Eustachian tubes when I equalized ( flu time) . Yes it hurt like hell and it wasn’t easy to fix at the moment. Instead of pinching your nose and exhaling to equalize, pinch and inhale to create a vaccum effect.

This ia a story that happened to an aquaintance. If you have any dental cavities, no matter how big or small, get them filled by a good dentist and also let him know that you are going to dive and need it to be filled so that no air can get trapped. He dove and got air stuck in his tooth ( he had a cavity) . Comming up, he couldn’t fix the air lock and the trapped air expanded. They pulled him into the boat with a bloody mouth and a heck of alot of pain.

Diving is really fun and rewarding as long as you don’t cut corners or overshoot your abilities. Best of luck to all from beginners to experts and have a great diving season!

By: gilligan0211

gilligan0211 — Fri, 26 Mar 2010 14:37:41 +0000

Hey Josh, I want to throw this out there. If you are not certified, go about finding an agency first! Find someone you are comfortable with and let them know your situation. If you have asthma and you lie about it on the legal forms beforehand, you may run into problems with insurance. There will be a form they need your doc to sign off on to release them of liability. It’s not a big deal, but they are generally very picky about this. Its a full blown medical history questionnaire they will need from you. Anything major that you answer yes to is going to be an issue right off the bat. I would hate for you to have to miss any of your classes. Once the open water is out of the way, the other classes just roll on by. Good luck!

By: Christian Nadeau

Christian Nadeau — Fri, 26 Mar 2010 12:43:51 +0000

I’ve thought about doing that but was leaning more towards SDI/TDI so I could get my solo cert along with Adv. Nitrox and Deco. I think I’ll look into PADI more though.

Chris

By: ITS Admin

ITS Admin — Thu, 25 Mar 2010 19:01:10 +0000

Awesome Josh, you should be good to go on diving, and sound just like my buddy that I dive with. He also does Crossfit and has no problem with going for his inhaler.
Be sure and let us all know what you find out! I can’t take credit for the Pegasus Missile comment, that came from one of my instructors in the military describing what he didn’t want to see during a water evolution LOL!

~ Bryan

By: Josh

Josh — Thu, 25 Mar 2010 18:17:20 +0000

Awesome responses, guys! Ive had asthma all my life, and when i was a child, i would have full blown asthma attacks that would leave me hospitalized, but im 27 now, and havent had an attack since i was in middle school, if that.

When i exercise or work out, i get winded and out of breath like anyone, but rarely do i resort to going to my inhaler. Ive ran 5K’s, done crossfit workouts and im winded, maybe more than everyone else, but i rarely feel the need to grab my inhaler to recover. Hopefully the fact that although i still have asthma, i can definitely function like a normal person when it comes to sports/exercise, is an indicator that i can in fact, engage in something like scuba diving

For now, im gonna go consult some physician friends of mine and see what they say, and investigate for any Hyperbaric Physicians around my AO

And Brian – i “lol’ed” at the “Pegasus Missile” comment.

By: Ashley Gill

Ashley Gill — Thu, 25 Mar 2010 13:45:56 +0000

Wow. lol everyone’s throwing in their 2 cents on the matter. Hmm.. :) Sooo Josh! I would agree with Gilligan0211 on this one.. just tape an inhaler to your mask. Or get a full faced mask and just tape it to the inside of that mask, then you can just rig a device so you can use it inside your mask. But then you have to think about the depth as they have said before. It might damage your lungs if you try to use it while you’re breathing O2 and Nitrogen. Soo.. as said before, I would talk to a doctor first before you do anything. Just to be on the safe side! :) My 2 cents is in! :D

By: Bob Tennant

Bob Tennant — Thu, 25 Mar 2010 01:16:58 +0000

Josh,
Bryan hit the nail on the head. Also, breathing air for diving is dehydrated somewhat and that can cause an asthma attack as well. If you want to pursue diving then look for a Hyperbaric Physician. They can run tests to see if you are truly fit to dive. Warning it may be expensive though. I have to that medical every 2 years because I am a commercial diver. Family doctors dont really know much about diving and usually error on the safe side.
Look on a Commercial Dive school website for doctors in your area.
Best of luck.