Working with charcoal cannot be a big no no, it was the only fuel used till about the 1800s and still is in many parts of the world.
When I have used charcoal, its harder for me to get than coal or coke, it uses a much lower air blast, needs to be a deep fire BUT you need to put a couple of bricks along the side of your fire to make is narrower. This helps achieve the depth but, more importantly stops burning the excess fuel. Charcoal will burn without an air blast so the fuel on the sides will burn but not contribute to your work, just waste fuel.
Its also got to be real lump charcoal not the BBQ brickettes.