Liquid Nitrogen dewar question

[Barker]

At what temp can you store a liquid nitrogen dewar. I am scared to keep it in the basement (70 degrees F) because I don't want to sufficate my dogs when they come in to sleep at night, but I wonder if the temp in my garage (90-105 degrees F in summer) is too hot. My basement is about 1800 square ft. with no outside ventilation.
-John

 

[Rob!]

The air you breathe is about 79% nitrogen. It would take a whole lot of nitrogen gas to raise that to a dangerous level. Your dewar should only boil off tiny amounts. I suppose a major spill might present a minor hazard - (or major if it was spilled on to someone).

The garage, however, should be fine. When you compare your basement temp to your garage temp, it seems like quite a bit - but in this case you are comparing both to the temp of the liquid nitrogen - and the difference doesn't seem like nearly so much. I'm not convinced it does much, but in the heat of summer, I keep an old blanket on top of the dewar - with the idea that minor boil off will keep it cooler under the blanket. I really haven't noticed any difference.

Disclaimer; 75% of the advice on the internet is wrong. It's up to you to decide where this advice falls.

Rob!

 

[Dan Gray]

personally
I wouldn't worry about it like Rob said we breath it anyway..
when the guy fills my Dewar you should see the vapors coming up around his head while the Dewar is cooling off and the LN is boiling off..you can't even see him for a while
in the room ,, this is a big gas outfit and they know what's safe and what's not to breath.. just don't let your pooch knock it over and walk in it, that I would worry more about.. JMO

 

[Barker]

Thanks guys. I'll probably just keep it in the garage. Rob, I think your right about the temp. 20 to 25 degrees prbably won't make a huge difference. The dewar is 22 liters, maybe I'll have to fill it a little more often.
-John