Do I actually need a respirator for woodworking, or is that overkill?
It depends entirely on how long you are in the dust. Occasional hand-tool work in a ventilated space is a different problem from hours of machine sanding. If you are only in dust briefly and rarely, a powered respirator is more than you need — and we would rather say so.
The useful question is not whether wood dust is bad for you. It is how much of it you breathe, for how long, and how often.
Hand-cutting a few joints with the door open is not the same exposure as a day on a drum sander in a closed garage. Machine sanding produces the finest particles in the largest quantity, and fine particles are the ones that stay airborne long after the machine stops and you have taken the mask off to sweep up.
If you are in that second category — hours at a time, regularly, machine work — the argument for powered air is not really about filtration. Any decent filter catches the dust. It is that you will actually keep it on. The most common failure of a sealed mask is not that it leaks; it is that after two hours of breathing through it you take it off.
If you are in the first category, buy a decent disposable, open a window, and spend the money on dust collection at the tool instead. That will do more for the air in your shop than anything you wear.
Related questions
Does the carbon pre-filter mean it handles fumes? Why do my glasses fog up under a dust mask, and what stops it? How often should a PAPR filter be changed? How long does a PAPR battery actually last in a working day?The Breathie Thingy
A powered air-purifying respirator for woodworkers. $499 for the first 30 units of each batch, including a spare filter kit.
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