My Mom just called me after getting home from some doc appointments. My cousin and her smelled some gas, and noticed the knob on the stove was turned a bit What must have happened was she knocked into it on the way out. My cousin helped her open the windows, and suggested we leave it like that for a while. I just called her back to make sure she had the dining room window open, not just the kitchen, so there is cross venthilation. Of course I goggled this, and also saw it's not wise to turn on or off the lights, that could cause a spark. That got me thinking about the microwave, I assume that's off limits too? Also, how long would it take for the gas to completely air out of the house??? Can we use the microwave tonight, and shut the lights, etc? She says we'll leave them all open till we go to bed tonight. I always check the knobs whenever I pass the kitchen, but was gone for work already. Now she will be full aware to do so as well.