The stipulation is that you can own a conventional stove if it is sized over 350,000 BTU. In the language, this is considered an "industrial" size that no homeowner would ever need. In an industrial application, theoretically, there are no residents to be bothered by the particulates in the smoke.
And here is where the guvment looking out for our own good runs smack dab into that little problem known as "unintended consequences." What happens is homeowners, like me, don't want a gassification unit for various reasons. Price, finiky, and just flat out don't want to be friggin told what we can and cannot buy and use on our own private property!!
So, we "oversize" our stove to get above that threshold and get a conventional stove.
Yet another example of guvment intrusion. If they would just mind their own beezwax and let the free market work itself out, we'd all be better off!