What's the normal lifespan of this equipment? I'd imagine this environment, particularly with the dust, would cause failure in the 5-10 year range rather than the 1-2 year range.
All equipment is within the operating specs
Modern equipment is pretty tolerant to high intake temps, due to lots of very poor datacenter designs. It's pretty common to see servers in older co-location facilities at the top of racks seeing 95F intake temps if the on-site staff don't really care about rack blanks and the like. These can go unnoticed for years and simply chug away with their fans at high speed.