I've been told that in Amsterdam, the fire code requires that pro dominatrixes engaging in bondage be able to get their customers out of any restraints within a set period of time (something like one minute). Does anyone know whether this is true or urban legend?

Well, that's one I'm pretty sure you won't be able to use the search engine for.
Someone can probably give you a link to the current code on such matters.
If you were coming to my house I'd wonder why are you interested in such a question?
Zack

lol I'm preparing a report on BDSM safety and, as you have noted, this is not an easy search to conduct via Google :-)

I've also been told that various houses have their own rules, so if anyone knows those, I would appreciate it