Gas Calcs

[Ian T]

Rather than reply to previous thread on Twin 80's at 200 bar, for Deep diving, I'm sure your TDI course would have clearly discussed, calculated and proven just what level of dive this would be safe for.

For 11L twins, for a 63m dive, you need a reserve of 180 bar. To do deeper (69m) you need 220 bar reserve, hence you can't do it. I'm sure you already knew this Harvs. However, these values are reserve needed to get you to 21m gas switch. These calcs also assume 20L/min SCR, and hence are inappropriate for you Harvs. (turning a dive in tank at H1 on thirds..... First time up G tunnel, JD and I were into the ballroom on thirds.... later calculated at 13L /min ).

[JD]

Ian,
Please remind me to discuss this with you over a red or 2 next weekend.

JD

[Ian T]

Sure can.

I have the Tech 2 pdf's we can work through if you'd like. Be good to chat about. As below, for deeper than 69m with twin 11L's, you would need stages in reserve, for gas sharing bail out. Anyway, we'll discuss this weekend

[ph]

Rather than reply to previous thread on Twin 80's at 200 bar, for Deep diving, I'm sure your TDI course would have clearly discussed, calculated and proven just what level of dive this would be safe for.

For 11L twins, for a 63m dive, you need a reserve of 180 bar. To do deeper (69m) you need 220 bar reserve, hence you can't do it. I'm sure you already knew this Harvs. However, these values are reserve needed to get you to 21m gas switch. These calcs also assume 20L/min SCR, and hence are inappropriate for you Harvs. (turning a dive in tank at H1 on thirds..... First time up G tunnel, JD and I were into the ballroom on thirds.... later calculated at 13L /min ).

Ian you are being very presumptuous about my sac rate...who turned a dive at H1 on thirds?