HEPA Filters: Bring in the Cool, Filter Out the Funk!

High Efficiency Particulate Air (HEPA) filters can remove at least 99.97% of airborne particles 0.3 micrometers in diameter. These particles are considered the hardest to filter and the Most Penetrating Particle Size (MPPS). Particles larger or smaller than 0.3 micrometers in diameter are actually filtered with higher efficiency.

The original HEPA filters were originally designed in the 1940s. They were used in the Manhattan Project to prevent the spread of airborne radioactive contaminants. They were commercialized in the 1950s. The term HEPA became a registered trademark and generic term for highly efficient filters.

HEPA filters are made of a mat of randomly arranged fibers. The key measurements that affect their function are:

-fiber density
-fiber diameter
-filter thickness

HEPA filters are designed to target small particles by trapping them (the particles stick to the fibers).

There are three different ways HEPA filters trap particles:

1. Interception: particles following a line of flow in the air stream come within one radius of a fiber and stick to it.
2. Impaction: larger particles are not able to avoid fibers by following the curving contours of the air stream and are forced to embed in one of them directly. This method gets better with less fiber separation and increased air flow velocity.
3. Diffusion: this is how HEPAs filtrate particles below 0.1 micrometers in diameter. The particles are impeded and delayed in their path through the filter which increases the chance that the particle will be trapped by interception or impaction.

Vacuum cleaners and air purifiers are probably the most popular appliances that use HEPA filters. You might want to cool down your air as well as get rid of contaminants, though. Enter the NewAir AF-330 Evaporative Cooler. This is the only evaporative cooler with a HEPA filter.

Evaporative coolers draw exterior air into special pads dampened with water. The air is cooled by evaporation and then circulated. This is kind of how our bodies cool down after exercising. We sweat and then the perspiration dries through evaporation and causes our body temperature to drop.

The NewAir AF-330 is a lot less noisy than other evaporative coolers because it uses a motor to rotate its synthetic pad instead of a pump to bring water to the pad. The pad never needs to be replaced either. There is a remote control for your convenience and easy control buttons on the unit itself.

Be sure to note that evaporative coolers should only be used in hot and dry environments. If there is humidity in the air, the evaporative cooler will simply add more humidity. The AF-330 works best when it is very hot and the humidity is below 50%.

HEPA filters can be a huge help to those suffering from allergies or asthma. They really help you protect yourself and your family from allergens, irritants and pollutants. If you need a cooling affect as well, try a NewAir AF-330 Evaporative Cooler. As mentioned before, it is the only evaporative cooler with a HEPA filter.