The exemption was attributed to cleanliness and good drainage.
The same old stateliness, the same cleanliness, the same stillness reigned there, and inside there was the same furniture, the same walls, sounds, and smell, and the same timid faces, only somewhat older.
The restaurant staff made sure that cleanliness was a priority in their kitchen.
Cereal pests can only be treated by general cleanliness and good farming, and of course they are largely kept down by the rotation of crops.
I prefer not to use public restrooms because they don't typically meet my standards of cleanliness.