I have two methods of dealing with the issue of sawdust in my workshop. Sawdust in my workshop is a problem because it makes a mess, gets all over everything, and creates a poor environment for applying fine finishes. I really don't do a lot of worrying about getting sawdust in my lungs, frankly.
The first tactic to keep sawdust out of the shop is to prevent creating sawdust in the shop as much as possible. Sanding is a poor method of shaping wood and a great method of creating sawdust. A sharp blade leaves a much better surface than an abrasive of any kind. Therefore, as a matter of habit, I use knives, planes, hand saws, and so on, as much as possible. On smaller hand-held power tools and my Brynes saw, disk sander and thickness sander, I and wherever else possible, I use a hose connected to my Shop Vac. Plane shavings are a lot easier to clean up and don't make any sawdust at all.
My second tactic for keeping sawdust out of the ship when more aggressive cutting is required, is to do that cutting outside the shop. I have all my stationary power tools on rolling stands and when I use them, I roll them outside the shop in the open air, or just inside the doors in bad weather. When I am using power tools that throw a lot of sawdust into the air, like table saws, planers, and wood lathes, I will also position a standing air fan to circulate the air from inside the shop to the outside to prevent the dust from entering the shop from the doorway area. I also have a separate area of my shop which serves as am office and "clean room" where no sanding is ever done. This enables me to spend a considerable amount of my shop time outside of areas where sawdust might linger.