Fumes in workshop

[Misty Smith]

There are laser fume odors in the work shop coming from the vicinity of either the blower or the laser machine itself (The front grid underneath the bed). There's no wood smoke in the cabinet and there's visible wood smoke outside where it exhausts on the roof so I'm leaning towards a blower or pipe leak.
How is the blower tested for leaks? The motor cooling fan is so strong that it immediately blows out a candle flame.

[Kev Williams]

If the blower is INSIDE and not OUTSIDE, then IT is the source of your fumes. The blower housing and all exhaust plumbing attached to it are under pressure; blower housings are not known for being airtight, and ANY place after the housing that air can escape WILL escape into the room.

case in point: I finally got the 2 blowers for my garage shop outdoors, inside a self-insulated patio storage box. I exhaust both blowers into a single storage box that I added a bunch of charcoal briquettes to help with the sound and smells (it works!) -- Each blower outlet has a louvered dryer vent inside the box, so when only one blower is running, the other blower's vent will be closed, and all the smoke will just exit the box. But what happens is, quite a bit of air & smoke just goes right past the closed vent and flows backwards into the non-running laser cabinet! I have blast gates on the all the blower vents that I can shut before the lasers, but there's still air leaks. So MY only fix is to exhaust each blower into a separate box, or run both blowers at the same time (which is what I'm doing at the moment :) )

So if your blower is inside, the only fix is to move it outside, then all the indoor plumbing will be in a vacuum condition rather than pressurized...

but if the blower IS outside, then your fumes are finding their way back in, thru a window or ventilation system, etc...

[Larry Robinson]

The leak would be on the discharge side of the blower. Is the exhaust pipe exiting the blower sealed?

[Craig Matheny]

move the blower outside

[Tim Bateson]

If you are using metal piping - BINGO! I switched to PVC and not only got rid of most fumes but also increased the draw.

[Bill George]

IF you can't put your fan or complete duct system outside and I was around a lot of commercial jobs that way, the sheet metal workers or tinners if you may used this stuff, Hardcast seen it done and it works > https://www.amazon.com/s/?ie=UTF8&keywords=hardcast+duct+sealant&tag=mh0b-20&index=aps&hvadid=78134098469961&hvqmt=e&hvbmt=be&hvdev=c&ref=pd_sl_6vr219t4a3_e