We have a good sized three stage HEPA filter ( two layers of foam with varying density, a carbon based filter for odor control and then the HEPA filter ) directly behind our work benches at the shop. This helps draw the solder smoke away from us as we work.
Other than that, soldering in a well ventilated area is the first and most obvious suggestion. Placing a box fan directly in front of you but behind the work surface and having it draw air away from you will help break up the smoke so that it is not so concentrated. This works much better than having the fan blowing at the work surface as that tends to cool the solder iron / gun too much and the solder joints may not set up correctly. Sean
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