On Tue, 24 Jan 2012 12:02:08 -0800 (PST), Amanda Ripanykhazova
wrote:

Does anyone know of a microwave which has a built in hood underneath
it which filters the air properly please?....
.... Mind you, the filters do go black quite quickly, which I
take to mean that they are filtering something: I think that the
standard way of cleaning them is with baking soda?

IMO, there is no such built-in that does an adequate job. When I acquire a new
kitchen, the first thing I do is to rip out any overhead microwave and install a
truly functional exhaust hood.

We run our filters through the dishwasher.

-- Larry