A friend of mine paints cars, motorbikes, guitars, whatever. He told me that when it's a hot summer he paints naked. The other option is to turn fans on (streaks the paint) or open windows (lets insects in).
I'm sure you could get a ventilation system that doesn't streak the paint, but he's a one-man-band and I imagine that would be quite bespoke (pricey).
He also used to work with a trainee who kept wearing aftershave that interfered with the paint... And no, I wouldn't want to see him working naked.