It traps it using a filtering system of hair and mucous.
Mucus
That would be mucus
Mucus traps dust, dirt. and other microscopic foreign particles from entering the body through the nose. It also warms up air that comes through the nasal cavity, which is why it is always better to breathe with your nose then mouth whenever possible.
to keep the germs away the hair traps the germs
Mucus traps dirt and bacteria.
tape
The hair inside your nostrils works like a filter, protecting you from breathing in potentially dangerous particles. Nose hair traps dust, pollen, germs and fungus so you don't inhale them.
Ciliated Epithelial Cells have tiny hairs on them. These hairs sweep away any unwanted things, such as bacteria and dust which is trapped in mucus.
Mucus helps in trapping pathogenic microorganisms and dust particles and prevent them from entering inside the lungs, second it keep respiratory tract moist so that friction is reduced. Another function of Mucus is to regulate the temprature of the inhaled air.
It traps bacteria and dust.
trap dust and germs and kill them