1.   It protects, primarily, by drawing all air in through a charcoal filter.

2.   Protect yourself by wearing a respirator with a charcoal filter.

3.   There are completely encased litter-box models available with charcoal filters.

4.   Under-Ease, with a patented charcoal filter system, eliminates bad odors so you can lead a normal, active life.

5.   In addition, they come with a charcoal filter to reduce toxic gases such as carbon monoxide.

6.   The electrical filter destroyed any bacteria, while the charcoal filter removed solid materials.

7.   In whisky they come from the charred insides of storage barrels, from the smoke used to dry germinated barley, and from charcoal filters.

8.   Pettebone said the chemical agents leaked in two vestibule areas attached to two charcoal filter banks.