Print Page | Close Window

Powerdive units

Printed From: The Fishing Website
Category: Diving
Forum Name: The Scoobie Gang
Forum Description: Tanks thanks! - SCUBA diver's here
URL: https://www.fishing.net.nz/forum/forum_posts.asp?TID=51649
Printed Date: 15 Jun 2026 at 1:45pm


Topic: Powerdive units
Posted By: ancient mariner
Subject: Powerdive units
Date Posted: 13 Mar 2010 at 1:40am
Just checked out their website and seems good.

One question, are dive tables still relevant with these types of setups?


Replies:
Posted By: Finatic
Date Posted: 14 Mar 2010 at 10:57pm
Any idea of what percentage of nitrogen are they pumping? I guess that would determine the dive table question.

I only thought these things were only good for about 5m. Quiet surprised with that Extreme Snorkel model.

Saw a guy diving off the back of his gin palace at Hooks Bay once. He was down for a fair time.


-------------
What's the cheapest type of meat? Dear balls. They're under a buck.

Posted By: Dagwood
Date Posted: 15 Mar 2010 at 6:21am
From what I can see, these are pumping straight air so standard tables / computer to avoid the bends would apply. Ascent rates would also apply. 

Posted By: Busted!
Date Posted: 28 Mar 2010 at 4:39pm
Also need to be bloody careful what you are pumping - eg all fumes, ciggie smoke, solvents, lpg, fuel vapours etc will go straight down ya gob if you park the inlet for the pump in the wrong place.
 
Tie the compressor to the boat - for the people that don't find this obvious once you run out of supply hose you are pulling directly on the pump...
 
Also, take a bail out bottle (spare air, scuba pony cylinder etc) with you as the greatest pressure change is in the last 10m before the surface.  A direct ascent to the surface from here can give you problems so you need an insurance system in case the supply pump fails...

Posted By: smelly nelly
Date Posted: 03 Apr 2010 at 12:01pm
i think you mean tie the hose off so that theres still a mt or two slack between it and the pump when the diver pulls it tight, as long as you were to breath out slowly on the ascent from 10mts you shouldnt have to many problems from that unless of course you had deco to do and omitted those stops on the way up,then you could have some problems

Posted By: Busted!
Date Posted: 04 Apr 2010 at 9:24pm
Yeah, used to word it that way.  Then heard a guy had done a free ascent because the air stopped coming...  He'd tied the hose off with thin line, and when he pulled it tight it kinked off on him - pulling the hose at 90deg to the feed off the compressor.  Probably not likely to happen again, but you never know!
 
Maybe it's better to word it "follow the instructions in the manual regarding securing the hose and compressor to the boat or platform"...
 
As far as the actual diving side, you're still breathing under pressure so the same possible problems could occur as with any shallow water scuba dive.  If you come up while holding your breath or being unable to release the air from your lungs, the expansion of the air could cause you one of quite a few nasty little issues.  Don't hold your breath basically, and don't dive if you feel like you have a head or cheat cold or have the sniffles.  Most rec. tables give you around 200 minutes from when you leave the surface until you start coming up from the bottom so DCI or "the bends" probably won't be an issue.  Safe way out is do the deepest part of the dive first, work your way up slowly and stop at 3-5m for a couple of minutes before surfacing slowly...  
 
Otherwise they are pretty good units, and have quite a few uses. 

Posted By: Don18025
Date Posted: 06 Apr 2010 at 10:34pm
Hookah units are popular with Aussie abalone divers. There was one I saw many years ago used on the Wellington coastline. The compressor was a standard single piston compressor run on vegetable oil, had two filters and water traps and a 5 hp Honda motor, the air intake was about 5 feet above the unit sitting on the back of the boat transom alongside the outboard. Most of the time the divers worked 30 feet even with 100 foot hoses. Had amate who thought about getting one, but since hen stuck to scuba.

Posted By: smelly nelly
Date Posted: 19 Apr 2010 at 11:21am
Originally posted by Busted! Busted! wrote:

Yeah, used to word it that way.  Then heard a guy had done a free ascent because the air stopped coming...  He'd tied the hose off with thin line, and when he pulled it tight it kinked off on him - pulling the hose at 90deg to the feed off the compressor.  Probably not likely to happen again, but you never know!
 
Maybe it's better to word it "follow the instructions in the manual regarding securing the hose and compressor to the boat or platform"...
 
As far as the actual diving side, you're still breathing under pressure so the same possible problems could occur as with any shallow water scuba dive.  If you come up while holding your breath or being unable to release the air from your lungs, the expansion of the air could cause you one of quite a few nasty little issues.  Don't hold your breath basically, and don't dive if you feel like you have a head or cheat cold or have the sniffles.  Most rec. tables give you around 200 minutes from when you leave the surface until you start coming up from the bottom so DCI or "the bends" probably won't be an issue.  Safe way out is do the deepest part of the dive first, work your way up slowly and stop at 3-5m for a couple of minutes before surfacing slowly...  
 
Otherwise they are pretty good units, and have quite a few uses. 
  your right you are still breathing under pressure,but at 10mts most people would be able to breath out to the surface comfortably,without running out of air and blacking out on the ascent, safe way would be be to look at your tables before the dive so you know exactly what stops and time you have to do

Posted By: Diver Dan
Date Posted: 19 Apr 2010 at 6:23pm
Diving with a hookah has its ups and downs - great not to have a tank on your back, but can be a pain being tethered. Perfect for ab diving. Slow ascents from 10m aren't a problem if the air stops.


Print Page | Close Window