02 breaks

Alan Mackenzie · December 15th, 2005, 01:41 AM

Hi All,

As ever I have another weird question which stems from my lack of knowledge. I've come across the idea of air breaks or cleanup breaks. What's the principle behind it? Does the air break time count as part of your deco stops or is it additional time tacked onto the deco?

ATB
Alan

Marcin Kaluza · December 17th, 2005, 09:50 PM

Quote: (Originally Posted by Alan Mackenzie)

What's the principle behind it?

The idea is that oxygen is a vasoconstrictor and it means that breathing it for prolonged time means that your gas exchange gets impaired. By how much nobody knows but it seems to be a goood idea to let your body rest for a while after breathing pure O2 for some time.

Quote: (Originally Posted by Alan Mackenzie)

Does the air break time count as part of your deco stops or is it additional time tacked onto the deco?

Some deco programs do support it and calculate your gas loading accordingly, but I think majority of divers just won't be bothered and count them as part of the deco. I think the general consensus is that you should think of back gas breaks after some 20-30mins at 6m on O2.

Best Regards

Jack · December 19th, 2005, 07:32 AM

Quote: (Originally Posted by Alan Mackenzie)

Hi All,

As ever I have another weird question which stems from my lack of knowledge. I've come across the idea of air breaks or cleanup breaks. What's the principle behind it? Does the air break time count as part of your deco stops or is it additional time tacked onto the deco?

ATB
Alan

12 mins on 6 mins off. Helps cool down the lungs as high (1.6 ppo2) o2 exposure can "fry" the alveoli in the lungs causing vasoconstriction .
With a 20 min 6m stop break it into 2 x 10 min with a break in the middle.

**Alastair** · December 19th, 2005, 09:02 AM

Quote: (Originally Posted by Jack)

12 mins on 6 mins off. Helps cool down the lungs as high (1.6 ppo2) o2 exposure can "fry" the alveoli in the lungs causing vasoconstriction .
With a 20 min 6m stop break it into 2 x 10 min with a break in the middle.

Jack, given your example are you not counting the break time as part of the deco time?

Thanks
Al

Andy Kerslake · December 19th, 2005, 09:20 PM

12 on 6 off is standard, with the off time included as part of the deco.

Andy

PS For the 20 minute example would probably do either 12 on 6 off (up) or 12 on 6 off, 6 up (on) depends how conservative or not you want to be.

Jack · December 20th, 2005, 03:18 AM

Yes Al, sorry. Andys post clears it up nicely.

Quote: (Originally Posted by Alastair)

Jack, given your example are you not counting the break time as part of the deco time?

Thanks
Al

GoDiva · December 23rd, 2005, 12:45 AM

Quote: (Originally Posted by Marcin Kaluza)

The idea is that oxygen is a vasoconstrictor and it means that breathing it for prolonged time means that your gas exchange gets impaired. By how much nobody knows but it seems to be a goood idea to let your body rest for a while after breathing pure O2 for some time.

I really need to find somebody who knows more about this all. The doctor I asked did not seem to give me a satisfactory answer to my question about the effects of breathing 100% percent oxygen, and certainly not after how much time this happened, and which aspect caused the problems (the high concentration in the lungs? The higher pO2 in the blood?). Anyway, I decided I could not continue my questions to the more difficult bit about oxygen above atmospheric pressure. I think I will have to pester some more doctors

.

I hadn't heard about the vasoconstrictor effects. It surprises me, als hyperbaric oxygen ("deco tanks") have an important role in the treatment of wounds which take a long time healing (eg. in diabetics or other patients where blood supply to the extremities is impaired).

Any experts on board?

Danny · December 23rd, 2005, 12:50 AM

I've you need some reading material about this ,just let me now.

GoDiva · December 23rd, 2005, 12:56 AM

Quote: (Originally Posted by Danny)

I've you need some reading material about this ,just let me now.

Definitely interested. Sadly I am out of diving for at least 10 days

(discovered the walls are closer to each other in the width then in the length of the swimming pool during the warm up of the waterpolo-training this evening

)

Danny · December 23rd, 2005, 01:03 AM

You know where to find me:-)

December 15th, 2005, 01:41 AM	#1 (permalink)
Alan Mackenzie(Offline) New Member Join Date: Nov 2005 Location: UK Posts: 5	02 breaks Hi All, As ever I have another weird question which stems from my lack of knowledge. I've come across the idea of air breaks or cleanup breaks. What's the principle behind it? Does the air break time count as part of your deco stops or is it additional time tacked onto the deco? ATB Alan

December 17th, 2005, 09:50 PM	#2 (permalink)
Marcin Kaluza(Offline) New Member Join Date: Dec 2005 Location: UK, Bracknell Posts: 30	Quote: (Originally Posted by Alan Mackenzie) What's the principle behind it? The idea is that oxygen is a vasoconstrictor and it means that breathing it for prolonged time means that your gas exchange gets impaired. By how much nobody knows but it seems to be a goood idea to let your body rest for a while after breathing pure O2 for some time. Quote: (Originally Posted by Alan Mackenzie) Does the air break time count as part of your deco stops or is it additional time tacked onto the deco? Some deco programs do support it and calculate your gas loading accordingly, but I think majority of divers just won't be bothered and count them as part of the deco. I think the general consensus is that you should think of back gas breaks after some 20-30mins at 6m on O2. Best Regards __________________ Marcin HLPlanner - free VPM-B based decompression software

December 19th, 2005, 07:32 AM	#3 (permalink)
Jack(Offline) Paddy Exley Join Date: Nov 2005 Location: Dublin Posts: 198	Quote: (Originally Posted by Alan Mackenzie) Hi All, As ever I have another weird question which stems from my lack of knowledge. I've come across the idea of air breaks or cleanup breaks. What's the principle behind it? Does the air break time count as part of your deco stops or is it additional time tacked onto the deco? ATB Alan 12 mins on 6 mins off. Helps cool down the lungs as high (1.6 ppo2) o2 exposure can "fry" the alveoli in the lungs causing vasoconstriction . With a 20 min 6m stop break it into 2 x 10 min with a break in the middle. __________________ Jack www.dublinbaydiving.com

December 19th, 2005, 09:02 AM	#4 (permalink)
Alastair(Offline) DIRX Supporter Join Date: Nov 2005 Location: UK Posts: 693	Quote: (Originally Posted by Jack) 12 mins on 6 mins off. Helps cool down the lungs as high (1.6 ppo2) o2 exposure can "fry" the alveoli in the lungs causing vasoconstriction . With a 20 min 6m stop break it into 2 x 10 min with a break in the middle. Jack, given your example are you not counting the break time as part of the deco time? Thanks Al __________________ Helium is our friend - GI3

December 20th, 2005, 03:18 AM	#6 (permalink)
Jack(Offline) Paddy Exley Join Date: Nov 2005 Location: Dublin Posts: 198	Yes Al, sorry. Andys post clears it up nicely. Quote: (Originally Posted by Alastair) Jack, given your example are you not counting the break time as part of the deco time? Thanks Al __________________ Jack www.dublinbaydiving.com

December 19th, 2005, 09:20 PM	#5 (permalink)
Andy Kerslake(Offline) Wreck and Cave Diver Join Date: Dec 2005 Location: UK Posts: 93	12 on 6 off is standard, with the off time included as part of the deco. Andy PS For the 20 minute example would probably do either 12 on 6 off (up) or 12 on 6 off, 6 up (on) depends how conservative or not you want to be.

December 23rd, 2005, 12:45 AM	#7 (permalink)
GoDiva(Offline) New Member Join Date: Dec 2005 Location: Belgium Posts: 547	Quote: (Originally Posted by Marcin Kaluza) The idea is that oxygen is a vasoconstrictor and it means that breathing it for prolonged time means that your gas exchange gets impaired. By how much nobody knows but it seems to be a goood idea to let your body rest for a while after breathing pure O2 for some time. I really need to find somebody who knows more about this all. The doctor I asked did not seem to give me a satisfactory answer to my question about the effects of breathing 100% percent oxygen, and certainly not after how much time this happened, and which aspect caused the problems (the high concentration in the lungs? The higher pO2 in the blood?). Anyway, I decided I could not continue my questions to the more difficult bit about oxygen above atmospheric pressure. I think I will have to pester some more doctors . I hadn't heard about the vasoconstrictor effects. It surprises me, als hyperbaric oxygen ("deco tanks") have an important role in the treatment of wounds which take a long time healing (eg. in diabetics or other patients where blood supply to the extremities is impaired). Any experts on board?

December 23rd, 2005, 12:50 AM	#8 (permalink)
Danny(Offline) New Member Join Date: Dec 2005 Location: Belgium Posts: 77	I've you need some reading material about this ,just let me now.

December 23rd, 2005, 12:56 AM	#9 (permalink)
GoDiva(Offline) New Member Join Date: Dec 2005 Location: Belgium Posts: 547	Quote: (Originally Posted by Danny) I've you need some reading material about this ,just let me now. Definitely interested. Sadly I am out of diving for at least 10 days (discovered the walls are closer to each other in the width then in the length of the swimming pool during the warm up of the waterpolo-training this evening )

December 23rd, 2005, 01:03 AM	#10 (permalink)
Danny(Offline) New Member Join Date: Dec 2005 Location: Belgium Posts: 77	You know where to find me:-)