View Full Version : Vote: SAC "emergency" factor for planning

08-23-2007, 12:02
One of the items that comes up continually in the SpareAir vs. Pony Bottle (vs. have a better buddy) debate is that your SAC rate will go up when you are faced with an emergency.

For gas management purposes, it seems that knowing your SAC rate in an emergency (I'll hazard calling it your "ESAC") would be important. i.e. if I wanted to make sure I had an adequately sized pony bottle, I had better have a realistic estimate of my air burn rate when the adrenaline is pumping from and encounter with a free flowing regulator at 100'.

OK, so...given that no one is going to take the time to note thier SAC when panicking...anyone have a good source for what a reasonable factor is to apply to your SAC to derive a reasonable ESAC for planning purposes?

OK, great STB....what say you? What factor should you multiply against your SAC to get your estimated ESAC?

Just a clarification: vote for what factor to multiply your SAC against.

So it would be voting for:
SAC x 1.0
SAC x 1.5
SAC x 2.0 etc....

I'm surprised that several have voted for SAC x 1.0 as what they use for planning for contingencies (of the staggaring number of 5 who have voted, including myself. I know....the response is overwhelming!)

Maybe it wasn't clear that I was looking for a multiplicative factor, not an absolute number to use (i.e. my SAC is .55, but I use 1.0 for planning <= this would basically be doubling your SAC, meaning vote for x2.0 in the above)

Cast your vote or post your rock-solid reference and we'll see if we can come to a consensus on this.


08-23-2007, 16:08
I double my normal rate for my emergency rate. But my bottle is larger than any air requirement I'd need because it's 40 cf.

08-23-2007, 19:21
I do my dive planning using a SAC of .5 for most low effort diving. I plan my bailout bottle with the same SAC. My actual SAC is somewhat lower than .5.

08-28-2007, 11:21
OK. So why did I choose to make this a voting thread???

I am facinated by this idea of the "Wisdom of Crowds".

From: http://www.randomhouse.com/features/wisdomofcrowds/

In this endlessly fascinating book, New Yorker columnist James Surowiecki explores a deceptively simple idea that has profound implications: large groups of people are smarter than an elite few, no matter how brilliantóbetter at solving problems, fostering innovation, coming to wise decisions, even predicting the future.


So don't be a lurker!!! Vote!! The more the merrier. :smiley32: