Understanding Vacuum Cleaner Filtration
Did you know?
A vacuum without a good filtration system is like using a leaf blower throughout the facility. In addition, poor filtration causes motor failure, excessive dusting due to dirt on the horizontal surfaces, and reduced indoor air quality.
With the growing concern for pollution control, filtration and indoor air quality have become a big issue in the sanitary maintenance industry. Without good filtration, the unwanted dirt and dust is simply exhausted back into the air.
Small particles are generally measured in fractions of a meter, known as microns. One micron equals one one-millionth of a meter. Particles below 10 microns are invisible to the human eye. However, the most common airborne particle is 2.4 microns. The most harmful Respirable Size Particle (RSP) is 0.3 microns. To put this in perspective, the diameter of the human hair is typically 80 to 100 microns.
A standard HEPA filter must retain all particles to 0.3 in size at 99.97% efficiency, thus retaining all harmful allergens. Filtration is measured in terms of airflow waterlift, particle size, surface area, and graduated filtration.
Just give me the facts….
Airflow determines how many particles can be moved into a vacuum cleaner in a given period of time. The speed at which this happens is called capture velocity. Capture velocity is the speed of the air rushing into a vacuum cleaner’s orifice necessary to overcome gravity, removing dust-laden air from a surface or space in the process. A capture velocity of 1,000 feet per minute (fpm) is sufficient for vapors, gases, and smoke, but a minimum of 5,000 fpm is necessary for lead dust with small chips, cement dust, and chunks of asbestos pipe insulation.
Waterlift is the term used to describe the process of a vacuums ability to lift water from a stationary position into the air-stream. The higher the waterlift rating, the stronger your vacuum motor is which, in turn, increases the capture velocity.
Useful information on the Henry-Vac
Compared with single motor upright vacuums, there is significant cost savings in:
- Less down time
- Less damage than an upright vacuum being banged into furniture and walls. Canister vacuums are less fatiguing for the user. The user is pushing and pulling more weight with an upright versus the wand and tool of a canister vacuum.
- The canister is lightweight and easy to handle with a low of center gravity.
- Ultra quiet operation. Perfect for offices and hotel environments.
- Standard HEPA-rated three stage filtration.
The effectiveness of a vacuum cleaner is also measured in the amount of air the vacuum can displace, measured in cubic feet per minute (cfm). The higher the cfm rating of a machine, the more dust-laden air and debris it can remove from a surface. The amount of air the vacuum can displace is dependent upon the speed and size of the fans in the motor, which gives a better cfm rating.
Filters are designed not to stay clean. The idea for a superior filter system is for it to capture unwanted particles while still allowing air to pass through the system. The size of the dust particles that impact the filter is the most important factor. Filters can be made of many types of materials, such as woven or non-woven fabrics or micro-permeable plastic tubes.
What does all this mean?
It means that when evaluating how good a filter works, two pieces of information are needed. First you need to know how small of a particle the filter will capture. As stated previously, particles are measured in microns. The second piece of information is the efficiency rating of the filter. This is the percentage of the stated micron size that the filter will capture.
The Henry-Vac canister vacuum outshines all the rest in terms of filtration. It achieves a filtration rating of 99.99954% at .3 microns and has a triple filtration system. Its waterlift of 96 inches and its airflow rating of 106 cubic feet per minute make this vacuum unbeatable in the sanitary maintenance field.