Well okay.
I've come to a conclusion about all this.
First I'm gonna get an exhaust fan or dye the leather outside. Of course that's if I use the solvent/spirit based dyes and also use proper equipment such as gloves and maybe a facemask.
Two I'm gonna make the transition from using solvent/spirit based dyes to the water based dyes.
Three I don't sand leather much but I do skive leather a lot. SO I would want to purchase a handheld vac just so it doesn't end up on the floor.
Four In any time I would use a sander or a spray, yes I would use a respirator.
But in any case I'm most worried about vapors. Especially if it's coming from the dyes. I use Fiebing's pro oil dye with a dauber.
As for glues I've already started using the eco-weld glue.
So far I like it.
I also do have a head knife but I always use the roller knife instead, just ease of access plus the round blade can be retracted with a button.
Okay thanks everyone.
I do feel a bit better.