Push the air or Pull the air

Wondering if anyone has opinion on pushing air through an enclosure or drawing it out via one of those inline duct fans at vent side.

I was talking to a fabricator and he recommended to pull the air out, while I myself think that pushing the air through & out would guarantee more constant clean air for the module to draw in for cooling.

The enclosure dimm’s are aprox (L)1,134mm x (735mm) x (H)400mm.
Sloped on front and back, front lifts up for access. Variable speed fan (12") on left gable and exhaust on the right gable…2.5ft rising vent pipe.

I “imagine” the pull version will clear the space, but how fast is the question…whereas I see the push air version as keeping a constant clean airflow except for maybee dead zones to the immediate left and right corners of the fan end…the exhaust end of the frame will have a 'smoke box tapered toward the duct out.

The enclosure I saw working had a lot of lingering smoke throughout and a 95cfm small diam (relative to the size of box) sucking like mad.
The Axial fan I found has a huge cfm 1300 at 56db but would probably do most work at low to mid speed so should be a bit quieter and less stress on the motor.

Any past experience or opinions!

I say pull, with the fan as close to the exhaust out of the building. The reason being if the fan is close to the enclosure and there are any leaks in the ducting the pressure will push smoke into the room. The same reason you don’t want to push air into the enclosure, it will force smoke out any crack it finds, not just the duct.

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Thanks Tim
Also reminded me to be sure about general air tightness.

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