If a shop has more than one laser engraver, does it need multiple fume extractors?

A single extractor can be used on multiple laser engravers. It’s important, however, to consider how the air flow will be distributed between them. Air likes to take the easiest path, so if one engraver provides more resistance than the others, that engraver will get less air flow even though it may need more. For this reason, if you are using a single extractor on multiple lasers, we recommend making sure that they are of the same model/size and as equally distanced from the extraction system as possible.   

   —BOFA International