Ventilation for injection molding setting

Hi - My question is about to select the best ventilation methods for a facility where about 5 to 10 small injection molding machines set up next to each other. Those injection molding machines are APSX-PIM full automatic desktop machines and they have been using mostly PP or PC plastic pellets. Our initial ventilation system was*SAS (Sentry Air Systems)*SAS-400-PFS*model for one APSX-PIM machine but it is not enough for more than two.*
Thanks
Kubi Kara
APSX LLC