That will be overkill, approximately 33,000Cubic foot /hour.
I'm not sure if you have the correct idea about extraction.
There are two ways of extracting fumes from a laser marking process:
For a fibre marking system, I would suggest that 4" tubing and inline fan will be powerful enough. Using 4" tubing means you can use standard products as used for venting or tumble dryers.
These videos may be of interest:
31 – Make Your Own Pre-Filter for MDF Fumes
31A – Fume Pre-Filter Design Mk2
I had one customer who vented out of the window and didn't realise that fumes were slowly coming back into the room. Her partner came in and was shocked at the concentration of the fumes.
If you do extract to air, I would suggest that you vent at least 10ft up (through piping if needed) or even better above the goof guttering.