The recent audio tape released by Al-Qaeda, warning more terrorist attacks inside the United States prompts us to take a pre-emptive measure of safeguarding ourselves by procuring safety equipment like gas masks.

Gas masks or respirator masks, are an essential part of protecting oneself from biological and chemical attacks. Respirator masks, however, are also frequently used for industrial safety on a regular basis. They can prevent the chemicals in paint and all manner of airborne pollutants from affecting your respiratory system. For those in the field of agriculture, a quality mask is essential.

There are three means by which respirator masks filter and purify the air: particle filtration, chemical neutralization, and chemical absorption or adsorption. Particle filtration uses a filter to block organisms or substances that are larger than the pores in the filter. Once the filter becomes clogged, it must be replaced to remain effective. Particle filtration gas masks, however, will not be helpful against chemicals and a different approach must be taken.

Chemical neutralization works by using a chemical to react with a particular substance, such as chlorine or ammonia, to make it non-toxic. Different filters are available for each type of chemical that needs to be eliminated. These respirator masks are ideal for industrial applications and the filters are coded by the National Institute for Occupational Safety and Health, a branch of the CDC.