Originally Posted by You want to go where?

Sorry, there are some intuitive leaps that may need to be made depending on what you read. Here is the very short synopsis. In the AC797 incident, there was a fire in the lav (not caused by smoking). However, in response to that incident, they required smoke detectors to be installed in the lavs, and, as a consequence, also banned smoking in the lavs. So, the ban on smoking lavs was imposed for safety reasons, but not specifically because a cigarette in the lav caused a fire. That said, the concern about people disposing of lit cigarettes in the trash was, I presume, a contributing concern. It was not the second-hand smoke concern which drove the later overall ban on smoking on planes.