 In our dry climate, we can seldom achieve that level. In the winter, that's our driest time of year, of course. I've done some trial runs in my house with the furnace, fan, and humidifier running for several days in a row. I can seldom achieve anything higher than the low 30s. That's not surprising, though, because the outside humidity in the winter can be 10% or less. The higher levels are indeed good for your floors.