If sawdust under a table saw catches fire, what type of fire extinguisher should be used?

When addressing a fire involving sawdust, which is primarily a combustible material, the best choice of fire extinguisher is one rated for Class A fires. Class A extinguishers are effective against ordinary combustibles such as wood, paper, and cloth. However, sawdust can pose a risk of creating a fire that could potentially spread to other materials, which may include flammable liquids (Class B) or electrically energized equipment (Class C).

Opting for a fire extinguisher that is rated for Class A, B, and C covers all bases by providing protection against a wider range of potential fire situations. In the event that the sawdust fire ignites surrounding flammable substances or electrical equipment, a Class A, B, C extinguisher ensures that you can safely and effectively tackle those fires as well.

Class D extinguishers are specifically used for combustible metals and would not be applicable to sawdust fires. Therefore, choosing a fire extinguisher that encompasses Class A, B, and C allows for comprehensive fire response in a workshop or similar environment where multiple fire risks may be present.