Once you have sealed a room with plastic sheeting and duct tape you may have created a better barrier between you and any contaminants that may be outside. However, no seal is perfect and some leakage is likely. In addition to which, you may find yourself in a space that is already contaminated to some degree.

Consider a portable air purifier, with a HEPA filter, to help remove contaminants from the room where you are sheltering. These highly efficient filters have small sieves that can capture very tiny particles, including some biological agents. Once trapped within a HEPA filter contaminants cannot get into your body and make you sick. While these filters are excellent at filtering dander, dust, molds, smoke, biological agents and other contaminants, they will not stop chemical gases.

Some people, particularly those with severe allergies and asthma, use HEPA filters in masks, portable air purifiers as well as in larger home or industrial models to continuously filter the air.

Face masks or dense-weave cotton material, that snugly covers your nose and mouth and is specifically fit for each member of the family. Do whatever you can to make the best fit possible for children.

Be prepared to improvise with what you have on hand to protect your nose, mouth, eyes and cuts in your skin. Anything that fits snugly over your nose and mouth, including any dense-weave cotton material, can help filter contaminants in an emergency. It is very important that most of the air you breathe comes through the mask or cloth, not around it.

Do whatever you can to make the best fit possible for children. There are also a variety of face masks readily available in hardware stores that are rated based on how small a particle they can filter in an industrial setting.

Given the different types of emergencies that could occur, there is not one solution for creating a barrier between yourself and any contamination in the air. For instance, simple cloth face masks can filter some of the airborne “junk” or germs you might breathe into your body, but will probably not protect you from chemical gases. Still, something over your nose and mouth in an emergency is better than nothing. Limiting how much “junk” gets into your body may impact whether or not you get sick or develop disease.