Inhalable wood dust

Very fine wood dust — 100 micrometers (μm) or smaller — can be inhaled into the lungs. Once there, the particles can (TODO) and cause cancer.

Even good dust collection systems in wood shops mostly get the larger particles. Smaller particles will hang in the air (or land, but then later be kicked up when disturbed). The best way to remove these is with an air filtration system. [1]

Resources

Dust sizes

See https://en.wikipedia.org/wiki/Particulate_matter#Size,_shape,_and_solubility_matter

Particle diameter	Name	Anatomy	Disorders	Notes
2.5 - 10 μm	PM₁₀ Coarse particles	Can deposit in the upper airways, including the nose, throat, and bronchi.	[1]	[source]
0.1 - 2.5 μm	PM_2.5 Fine particles	Can penetrate deep into the lungs, reaching the bronchioles and alveoli.	[1] [2] [3]
< 0.1 μm	PM_0.1 Ultrafine particles	Can traverse the alveoli's cell lining and enter the blood stream.		Not a concern with wood dust, but can be an issue with silica.

Dust sizes — Academic journals

In academic journals, three different sizes of wood dust are discussed:

respirable wood dust —
tracheobronchial wood dust —
extrathoracic wood dust — Wood dust that makes it past the larynx and into the chest. Most of this gets deposited in the alveoli.

"Human respiratory tract deposition modelling showed that the deposition of the particle surface area in the size range of 0.3–10 μm was mainly in the extrathoracic region, and the particle surface area in the size range of 5.6–560 nm was mainly deposited in the alveolar interstitial"