Mucus is typically used for trapping dust particles and bacteria, so where mucus itself is pretty sterile, there's all sorts of gunk attached to it.
the flower is sterile
If a sterile field becomes "contaminated" with a sterile solution, the field remains sterile.
sterile gloves
The physician inserts a moistened, nonlubricated vaginal speculum. After the cervix is exposed, the physician removes the cervical mucus. Next, he or she inserts a sterile cotton-tipped swab into the endocervical canal and rotates the swab.
No it's not sterile
The only place that these membranes have cilia is the upper respiratory tract. This upper part is called the mucocillary escalator. It helps to keep the lower tract sterile and remove mucus. You swallow this mucus and microbes and the strong acid in the stomach kills them. There are other openings to the outside, the oral cavity, urogenital canals and the digestive tract at the anus. All have mucus membranes. These protect the underlining tissues and entrap microbes as well.
sterile
This definition is only one or the other. Either sterile or non-sterile. There is no such thing as partially sterile.
The word "mucus" is used with mucus membrane; mucus membrane secretes mucous.
Sterile is clean and clean is sterile, so both
Are mucous membranes sterile
sterile