Friendly reminder - science can kill you!

2 weeks ago, I started a Bohemian Pilsner and put it in my fermentation chamber (chest freezer). A week later, I needed to take it out for a diacetyl rest. I had removed the BrewHauler harness for some other batches of beer, so I needed to work it back onto the carboy so I could lift it out of the freezer (I know, I know, I need to order another set).

So I opened the freezer, leaned in, and gently tilted the carboy as I worked the BrewHauler harness underneath so I could get them clipped.

Anyone see where this is going?

I started feeling lightheaded. Dizzy.

Do you see it yet?

CO2 is heavier than air. In a sealed chamber (like, oh I don't know, a CHEST FREEZER), it will sit there, odorless and colorless, waiting for an unsuspecting nincompoop to lean in and breath deeply as they engage in physical exertion. And a week's worth of fermentation is more than enough to fill a chest freezer with the friendly gas.

Don't stick your head in your chest freezer and assume you'll be able to breath normally. Ventilate before you lean in and do stuff. Or stand up, take a deep breath, then lean in and do what you need to do. But mainly, just be aware that the air inside your chest freezer fermentation chamber is NOT normal, breathable air. It's likely almost entirely CO2.

Thankfully, I realized what was happening before I passed out and hurt myself.

Glad you made it out unscathed.

Every time I've sniffed a bucket the CO2 burned my nose pretty bad. How did you not feel that?

Homercidal said:

Every time I've sniffed a bucket the CO2 burned my nose pretty bad. How did you not feel that?

Click to expand...

I guess maybe it wasn't 100% pure CO2, but rather a mixture with the air as I leaned in? I did notice it smelled like the fizz from a glass of soda pop, but it didn't occur to me that it might be a high enough concentration to actually impede my breathing and induce hypoxia.

A fan really helps out in this sort of situation. Regards, GF.