Actually, feather dust is a respiratory health concern whether you use deep litter or not.
Maybe a little less of an issue with some deep litter systems than with systems that have you stirring it up a lot with weekly clean-outs.
Commercial poultry industry workers have, if I recall, truly alarming rates of respiratory disease, despite using respirators and usually very aggressive ventilation. Too many birds in too little space.
Deep litter oughtn't be any dustier than non deep litter (tho obviously it is dustier than housing chickens on bare wire)... you don't START with the litter being deep, you just add more as required.
The usual knock against deep litter is *moisture*, as indeed it can be a bit damper than regular litter depending on how it's managed and what your ventilation is like... but damper litter is *less* dusty not more.
A fan blowing out the coop window is not going to do much of anything about dust. Either the coop is dusty or it's not, you know? However you do always need ventilation and it should be of a type not to let strong gusts of wind stir up the litter. Fan-operated ventilation is not generally necessary as long as you have a well designed system of 'normal', passive vent openings.
I was concerned about this 'dust' too. Someone brought me a bag of 'Aspen' Pet bedding. It says its made of hardwood and processing virtually eliminates any dust and it has NO aroma from oils. NOW, my question is, is this ok to put in the coop. I don't know if its cedar, it doesn't smell like anything... is this ok to use? I didn't pay for it, so I don't want to waste it.
With questions about dust and all, I have a question to add to this, it that is alright. We are attending the Chickenstock in our state in about 2 - 3 weeks. We might get our first chicks there. We know the coop we want to build (we think), and we are thinking of using some pine straw for litter and using the deep liter system. We have plenty of pine straw on our property. Would there be any concerns with using it exclusively? Should we add something else to the bedding?