That's not clear at all. The smoke from some toast burning and the smoke from your kitchen being on fire aren't necessarily the same in amount/duration/composi

That's not clear at all. The smoke from some toast burning and the smoke from your kitchen being on fire aren't necessarily the same in amount/duration/composition/distribution. Obviously an ideal detector would take such things into account and reject false positives. I do not know the degree to which this is possible in practice, but certainly it's been true basically every place I've lived that the smoke detectors very rarely reacted to "typical food burning incidents."