Some interesting questions?

[Fishkiller]

First things first

Warhammer basic math

I have a total of 2 tanks which are 121 cu ft LP steel. Fill each one to normal safe pressure it will hold 125 cubic feet of air, then add a few pounds of pressure because the burst disk hasn't blown ADD them together you have 265 cubic feet of air availble

Belushi
I appologize for condensing my tank type a 121CFT LP tank made by Farber painted white with Sherwood K valve 3500 psi burst disk


More on that so you stay under the water for say 4 hours at 35 feet, how do you handle a DECO DIVE from 30 feet?

 

[MrMrEZG]

Originally posted by Fishkiller
First things first

Warhammer basic math

I have a total of 2 tanks which are 121 cu ft LP steel. Fill each one to normal safe pressure it will hold 125 cubic feet of air, then add a few pounds of pressure because the burst disk hasn't blown ADD them together you have 265 cubic feet of air availble

Belushi
I appologize for condensing my tank type a 121CFT LP tank made by Farber painted white with Sherwood K valve 3500 psi burst disk


More on that so you stay under the water for say 4 hours at 35 feet, how do you handle a DECO DIVE from 30 feet?

1st a 121cft LP steel made by faber is rated for 2400 and if it has a + behind the # (2400+) then it safe to increase the pressure by 10%. it is NEVER safe to fill a LP tank to 3500. I hope I am not anywhere near where that is happening. Also yokes are not designed to handle that pressure for anything above 3000psi/200bar you need to go with a din set up.

2nd you can do a deco on that tank, as long as it can supply you with the air that you need.

and yes to the other questions.

 

[Se7en]

Q1
From memory, at 10.5 metres (circa 30 ft) Padi tables give you 218 minutes of bottom time. Navy table give something like 400 minutes, so we'll ignore those...
121 cuft air = 3267 litres, / 218 minutes

therefore you need a breathing rate of less than 15 litres per minute... at the surface. At 2 atm, you use twice as much volume, (effectively giving half the tank capacity) so your breathing rate would need to be the equivalent of 8ish litres per minute at the surface, or two breaths.

Good luck...

Q2. I talk... others might listen... makes me happy anyway.

I like my BC, and I don't have a yard...

Mike

 

[Fishkiller]

Ok so I thought it would be interesting. You are on a dive and just enjoy yorself so much that you don't want to surface, your at 30 feet and your computer goes in to DECO, I guess my original question should've been what would the procedure be? Go to 15 feet and wait until your air runs out? A little tounge in cheek Your buddy from the boat is asked where you are at? answer oh he's five feet below me



MrMrEZG I in all honesty will never let my 2400+ tanks be filled past 2800. that is pushing the + another 160psi my justification is all the wasted air putting gear on Checking Lp inflator on BC adjusting tank strap with my MARES Airlock etc.

 

[Se7en]

You would almost never see your computer go into deco at 30 feet - due to the way RBT increases with decreasing depth on a multilevel dive. You normally find that even if you are in deco at depth (slightly), it's cleared by the time you hit 30 feet.
Run some multi level profiles, and you will see what I mean.

However - it's _never_ a bad idea to spend as much time as you can at 15 feet... but I'd define 'as much time as you can' as still leaving you and your buddy 50 bar to ascend and get out of the water with. If I ever suffered a computer malfunction at depth, or where I though I was pushing the no deco limits, my action would be exactly that - ascend to 5m with buddy, and hang there for as long as I could.

Mike

 

[Fishkiller]

Originally posted by Se7en
You would almost never see your computer go into deco at 30 feet - due to the way RBT increases with decreasing depth on a multilevel dive. You normally find that even if you are in deco at depth (slightly), it's cleared by the time you hit 30 feet.
Run some multi level profiles, and you will see what I mean.

Mike

Thanks

I will this weekend