When pumping up tyres I leave the barn door open and take the cover off the wing so it gets enough air.
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It's just going to be noisy for the kids/missus sitting in the car whilst you pump up in the rain etc
It's not too bad really.
I have the compressor under a passenger seat. To protect the compressor from water ingestion, I ran a hose and mounted the filter in the quarter panel trim. As a bonus, the noise is greatly reduced.