12 nov 2004
>what is the humidity outside? if it is lower than inside, try opening the
>windows and running a fan to circulate the air.
rh works if the outdoor temp is lower. otherwise, use absolute humidity,
ie ventilate when wo < wi, ie ln(ro/ri) < 9621(1/(460+ti)-1/(460+to)).
for example, if it's 70 f and 80% indoors and 80 f outdoors, ventilate
when ro < 0.8e^-0.336 = 0.57, ie the outdoor rh is less than 57%.