An A-B-C or A-B-IIIE class powder extinguisher is most suitable in my oppinion. I have a 12 kg extinguisher in my workshop but even a 6kg extinguisher makes a huge difference. Im my oppinion it pays off in the long run to buy a good quality extinguisher from an industrial supplier and service it annually and have it pressure tested every 10 years. Cheap supermarket extinguishers cannot be serviced and the cost adds up over time if you buy new often enough to have one that actually works in an emergency situation.
They are safe for electricity up to 400 volt which is the highest voltage you may find in a modern workshop with three phase machinery. Single phase machinery only uses 230 volt.
I also have a fiberglass fire blanket hanging on the wall. A proper one. Some of the cheapest ones have proven to be super flammable.
I don't like carbon dioxide extinguishers as a fire in a woodworking workshop will likely spread quickly all the way up to the ceiling and carbon dioxide cannot be used to extinguish from below. I don't like foam because it leads electricity and a workshop is full of electrical cables which will likely be involved in a fire.
Just my oppinions......based on what I learned when I took the hot works certificate.
