I am in a new build and have a flue for a stove, also connections ready for gas or electric. I had a modern stovax put in, fully conforming to the new regs, multi fuel. Sweep is actually coming tomorrow. Most particle problems seem to come from old stoves and from burning un-seasoned wood, also from having the stove burn at too low a temperature
I put a flue thermometer on the flue, to help me get the optimum temperature for clean burning. I still have some kiln dried logs stored, also a stash of bord na nona briquettes, which I will not be replacing. My coal bunker is full of smokeless anthracite eggs and I have a few more sacks in the garage. It has been trial and error to get the cleanest, most efficient fuel but I will, eventually, only be using the smokeless eggs
My flue is straight up with no bends. Last house had a bendy flue and the fire cement sealing the joints, would sometimes crack. I could then smell the wood smoke while the wood pellet stove heated up. There was no smoke when it was up to temperature. Same with any stove or fire, slow burn with wood, will produce particles and the worst for that is wood that is damp deep inside ie not properly seasoned