It's been a long time since I've been in a chem lab but I've always wondered - if this blanket of CO2 magically protects fermenters
all over the world, why (when it is really calm with no wind blowing
) don't really short people have trouble breathing? After all,
air is made up of Nitrogen, Oxygen, Carbon Dioxide and other gasses so the CO2 should fall to the bottom...?
On a more serious note, if your sanitation is up to scratch and your ferment kicks off within a day or two, I wouldn't be too worried.
What is this "blanket of CO2" going to protect you from? Not infection. Not fusels. Not a poor recipe. Not poor yeast health. The CO2 is more about preventing oxidation than anything else.
By the way, test yourself. If air is made up mostly of Oxygen, Carbon Dioxide and Nitrogen.....before you google it..... write down
what percentage of each gas is in "AIR". (Assuming the other gasses are near enough to zero).
If you came close, give yourself a cigar, because I failed miserably.
Cheers,
smudge