In the precautionary statements, states 0.19% is flammable, so guessing that may be the actual percentage of CO in it.
So 0.19% would be 1900ppm, which should be enough to set an alarm off, but shouldn't otherwise be that dangerous as you're not breathing the pure contents of the can, which is small in comparison to room volume.
(Also, if you were, the lack of oxygen would get you first!)
