I spent about 6 months in the composite repair shop in the MRO I used to work in. Used to make carbon fibre repairs quite often (mostly airbus floorboards as I recall). When working on the stuff we wore filtered face masks and worked in a well filtered room with large suction machines to catch any stray dust and were always warned the fumes when cooking the panels were extremely carcinogenic. If I saw a carbon fibre fire I would keep quite a distance