I have used the small canned air from testors and paasche on a few occasions now. Does anyone know what the max PSI of the canned air is? I am using the small rubber hose that comes with the can adapter. (if that makes a difference). I have a small compressor from harbor freight that is friggin loud and dont like to use. I have also thought about buying one of those five gallon portable tanks and using the compressor to fill it. IN ANYCASE…what’s the PSI of canned air? 
That would depend on the atmospheric conditions and the temperature of the can.
Continuously reducing during use as the can get’s colder - nozzle size will also play a part.
I googled this, and found some discussions. One discussion said Freon at room temperature was about 70 psi. But the discussion said Freon had been replaced by gases like Butane. Looked up butane and at room temp it is about 120 psi.