When it comes to dry extraction carpet cleaning, “The trouble with our friends in the carpet cleaning industry is not that they’re ignorant, it’s just that they’ve been told so much that simply isn’t so.” (with apologies to Ronald Reagan)

These days the majority of industry experts should really be called wet extraction cleaning experts. Their understanding of dry extraction is on a par with a tuba player explaining how to play a violin – he knows music and music theory; but if he hasn’t played a violin, he will operate it improperly yet expect to hear music. Dry extraction is often maligned and little understood. Let’s put the record straight. The major difference between dry extraction and wet extraction is the amount of water & detergent used per square foot and the technology of how the liquids are controlled. The term extraction means removal. Both dry and wet extraction systems remove the sticky dirt and spots from the carpet by vacuuming. The critical differences are the type of vacuuming that is done, the amount of liquid used during the cleaning procedure and how the liquid is controlled.

For example, dry extraction vacuuming is done with simultaneous pile lifting and vacuuming; a teaspoon of liquid is used per square foot of carpet; and the liquid is controlled by moistening micro-sponges. So how does carpet soil? Carpet pile, cut or loop, makes the fabric a vertical surface (wood flooring is a horizontal surface). Once installed, the carpet begins to do its job of trapping and holding dirt, dust, and allergens which are brought in from outside on people’s shoes. Research has shown that the majority of the dirt on a carpet is carried in from the outside or from horizontal surfaces inside on shoes. This dirt can be divided into two categories, dry dirt and oily, sticky dirt. The dry dirt represents up to 85% of the total dirt that is walked in on people’s shoes. The oily, sticky dirt represents about 15% of the total. So carpet maintenance strategy concentrates on the most highly trafficked areas of the carpet in order to keep the whole carpet clean. The dirt will build up where people walk.

The objective of cleaning is to remove this dirt before it is tracked by shoes farther and spreads throughout the facility. This involves vacuuming/pile lifting as well as chemical cleaning. The HOST Dry Extraction System does both. Dry extraction cleans carpet using a controlled amount of liquid. The liquid is typically a blend of water (mostly) and a small amount of detergent and other green cleaning chemistry. Green Seal certified dry extraction methods today do not contain any petroleum solvents. In the past some did contain a small amount of solvent; but today these have been eliminated in favor of green cleaning chemistry. This controlled amount of liquid, roughly 1 teaspoon per sq. ft., is enough to dissolve the dirt, but not enough to lose control of it deeper down into the carpet pile. While this small amount of liquid dampens the carpet during the cleaning procedure (the amount of liquid @ 1 teaspoon per square foot compares to 40 times that amount with typical wet extraction systems) the carpet is dry and ready for traffic when the cleaning is done.

The millions of small, absorbent particles dampened with the right amount of water, detergents and green cleaning chemicals control the liquids at all times during the cleaning process. The objective is to avoid soaking the carpet or causing wick back of spots and soils a day or two after cleaning. The HOST Dry Extraction Cleaner is just like a sponge you might use in your kitchen to wipe up spills on a table or counter. When you pass the sponge across the surface, it lays out a film of cleaning agents, which dissolves the soil. Everything that is dissolved is absorbed and trapped in the HOST cleaner so it can be removed by vacuuming. This is the controlled and efficient way of removing dirt and spots from a carpet.

Proper cleaning with a dry extraction system involves a machine designed for the purpose plus the cleaning “sponges”. The dual counter-revolving brushes of the HOST machine open and revive the carpet pile allowing for more effective removal of the deep down dry dirt. The powerful vacuum deposits this dirt in a bagless hopper. After this thorough vacuuming/pile lifting, the HOST cleaner is applied to the carpet. The HOST machine brushes the moist HOST Dry Extraction Cleaner up, down, over and around the carpet fibers so they contact all surfaces of the soiled fibers, breaking the oil bond and wiping the soil away. The HOST cleaner absorb the dirt and spots and hold them. After brushing in several directions so as to bring the HOST cleaner into contact with all surfaces of the dirty carpet yarns, the HOST cleaner are vacuumed (extracted) out of the carpet with the HOST machines powerful vacuum.

Position on Interim, restore, overall cleaning

Another area of confusion is the industry’s use of the terms interim, restorative and overall when discussing carpet cleaning and/or carpet maintenance. When these terms are applied to wet extraction methods, we have no objection. The manufacturers and users of the wet extraction methods have the right to define it as they see fit. However, when these terms are applied to dry extraction theory and practice we must object.

Interim has been defined by the cleaning industry as a cleaning process that is done in between other more effective cleaning processes. The logic goes: there isn’t time to do the job right. Ultimately this leads the listener to the conclusion that interim cleaning methods are a useful cosmetic, but ineffective for actual cleaning. However, when one understands that carpets get dirty incrementally, in areas where people walk, and that dry extraction is designed to remove (extract) that dirt as it accumulates, the need for something more is unnecessary. Dry extraction removes the dirt that is there as a result of traffic, keeping the carpet clean and preventing the soil from spreading. No other step is needed.  For this reason, we do not use or recognize the word interim when discussing dry extraction cleaning.

Restoration is defined as cleaning a carpet that is soiled to an excessive level that requires extra effort and cleaning chemistry to get it clean. It is also assumed that only wet extraction can accomplish this difficult job. With a proper maintenance strategy and dry extraction tactics, as described above, a carpet need not ever reach this level of soil. If it does, any method that extracts the soil as it cleans is capable of “restoration”. Meanwhile, the HOST eVAC and SPONGES effectively restore trashed carpet without the extra cost of returning to a job to correct streaks and wicking that may appear after the carpet has dried.

Overall is defined as cleaning a carpet from wall-to-wall. It is usually suggested that this is needed once a year even if the carpet has been kept clean. When using the dry extraction system, overall cleaning is only needed if the carpet has never been cleaned, or if previous strategies have failed to control the dirt allowing it to spread throughout the carpeted area.