If you keep the windows open and perhaps run a fan, and don't spill any bongwater, I would say that it takes no longer than a day to air the place out.
Your parents were once as young and stupid as you are now so you're not pulling the wool over their eyes. You might as well just come clean with them cause they've probably done everything that you think you're hiding from them.
Smoke it outside. It gets into fabric if there's lots of smoke.
That smell will never go away. It will be in the carpet and furniture and stuck on the walls. You gonna get busted fool
in the room; 3 hours, on your clothes- 1 hour
At least an hour.
My parents are going on holiday abroad for 6 days and I wanted to get completely baked with 3-4 friends. We'll be smoking a large quantity, how long would it take to completely air out the whole flat?
