
Remember also there are seasonal variation in ms symptoms and high humidity is definately something to be aware of.
Hanging washing out to dry around the home is a big "don't do it" Showering or bathing in poorly ventilated living areas is another risk factor, so is cooking in pans on the stove, all will significantly increase the humidty. Warm summer air holds far more moisture than cold winter air too.
If you suspect humidity might be high, obtain a humidity meter and take some readings in your home over a week or so.
Hope this is of some use
Andrew