Anyone but a bedouin would call the terrain hereabouts a desert. The Mojave has no dunes, saguaro, or cholla but does have Joshua trees, lots of sage, scorpions, snakes and barren, wind-sculpted land, plus next to no rain. In any event, the region is dry as dust and the humidity is laughably low.
I learned something recently. As usual, it happened the hard way. Our winter place here was new when we moved into it. Local water is hard, so the house came with a water softener installed. Most softeners, including ours, utilize salt (NaCl) as the softening agent.
We recently decided to buy a portable humidifier to add some water vapor to our indoor air. Our hope was of having somewhat less dry skin and eyes. I filled and refilled it with tap water from the nearest sink in the bath and set it to "vaporizing."
Over a couple of weeks we noticed the house getting much dustier than usual, and wondered if the humidifier somehow was causing it. It was the cause. What we perceived as dust was in fact fine particles of salt from the softened water, settling out all over the house.
I finally remembered that the kitchen sink is supposed to provide unsoftened water, and began filling the humidifier there. Problem solved. What we saw immediately was that the plume of unsoftened water vapor rising from the humidifier's spout was less visible. It didn't contain salt particles that could not evaporate into room air.
The instruction manual for the softener didn't warn us of fallout from softened water. I suppose one would ideally fill humidifiers with distilled water, but that would be a huge hassle and at least somewhat expensive. The lesson is don't use softened water in a room humidifier.
