1. Newly renovated or renovated dwellings.
2, there are old people, children, pregnant women, newborn dwellings.
3, have asthma, allergic rhinitis and pollen allergy person's residence.
4. Keeping pets and animals in their homes.
5. Accommodation which is more closed or affected by secondhand smoke.
6. Hotels, public places.
7, willing to live in the high quality of the people's residence.
8, hospitals, reduce infection, prevent the spread of disease.