[imperialstout]

Just got, rather made, an oxygen aerating wand to use with an oxygen welding tank. Heat garage with a portable open flame kerosene heater. What precautions should I take to prevent the wort from bursting into flame? Plan to aerate at most 90 seconds. Kerosene heater is about 10 feet from the brewing bench.  Garage is 5K CF (21x28x9). Will have a through-the-wall ventilation fan installed before brewing next time. It draws about 800 CFM. Am thinking need to do nothing. Any excess oxygen bubbling out of the wort, which I keep to a minimum, will be vented outdoors in short order. Just the same, wanted to know what your experience has been with open flame heating and aerating with oxygen.

[a10t2]

5000 cu ft is ~140,000 L. You're going to be putting out something on the order of 1 L of O2, but let's say it's 10 L just to be conservative. That would increase the oxygen content in the garage from ~20.946% to ~20.953%. You'll probably be OK.

[narvin]

Turn off the heater for 10 minutes just to be safe in case of leaks.

[Jimmy K]

With an exhaust fan I think you're really safe.

[hubie]

You will be fine regarding the O2 you're dumping into the garage.  What I'd be more concerned about with the close proximity of the heater is the potential for doing something careless like moving or laying down the wand too close to the heater while the wand is putting out O2.