Connecting two torches to vent
 

Hi its been about 5 years and I've forgotten so much
I'm sharing a space with another person who is also a newbie, and doesn't quite understand the need for really good venting of fumes/gases.
I need to figure out a good vent system for two torches, somehow.

I have a squirrel cage thing.(fan) there is a space(hole) above the torches in the wall for an exhaust system I don't know how to set it up for two torches, before I had a DH who did that...one is a Bethlehem cuda and the other a bravo, using three oxy boxes.

I understand about cfms and intake/outflow air and I don't quite understand how to have two separate sucker ducts Ie one behind each torch connected to a single outflow…There is also a serious outflow fan assembly available

I looked on Grainger and they have a tabletop 8 inch filter box assembly, but it looks like it is plastic and no cfms even listed. I remember Glasscraft inc used to have a tabletop vent that was rated for a bethelehem bravo....

Any ideas, please!!

thank you kindly