Since the relative humidity outside is 40%, the partial pressure must be 0.40 x 0.085 or about 0.034 atm. The relative humidity at 20 C would therefore be 0.034/0.025 = 136%. It literally rains inside the laser lab during the summer. The big laser tables become damp with condensation and we have to purge the entire laser system constantly with dry nitrogen to avoid destroying our water-sensitive optics. What a mess!