So.. I came home and the whole house smelled of gas as if a stove knob had been left open

I quickly checked all the stoves in the house and found one on......I quickly turned it off ....and opened all doors to ventilate the house ....how long do I wait to turn on a stove now? It was apparently on all night. And we get gas back at around 3 to 4 am a D it's now 6. So it's been in the air for like 3 hours or so. How many hours do I wait?