planes develop leaks along their lives and I remember one flight attendant telling me how they proped a piece of soap in the lavatory basin drain...this would suck all the foul smelling odors out of the lavatory...but affected our pressurization especially in a reduced power descent.
I don't understand the reason for the pressure differential in a lavatory that explains the above.
Does this mean that if one were to seal the lavatory from inside using wet cloths etc. around the doors and then left the sink drain propped open that you would eventually suffocate ? Or just smoke your ciggie with your head over the sink basin.