Daytime humidity during summer where I am is typically less than 30% - usually low 20s, not uncommon for teens, and occasionally single digits - humidity does go up a fair amount at night, but I would think the "average" humidity per day wouldn't be much of 40%.
I don't do anything to increase humidity - I just water as needed. Most commonly grown orchids, such as commonly found Catts, Dens, Phals, Onc - should be fine with the humidity you have
Well, it sounds like my humidity level is acceptable. I will try humidity trays and grouping plants together. I did have an old vaporizer that I tried. It only raised the humidity by 1%. Sheesh. Not worth the effort.
I have found that air movement is more important than humidity (if one has to choose/compromise). Moss that stays moist for over a month sound dangerous... Temperature should not go far below 10 deg c and far over 30 deg c. I just installed a 400w MH globe and my orchids ( dendrobiums and angreacums) live side by side, seemingly happy.