Game Plan: Suspended Soil Removal
The purpose of the “Game Plan” is to explore in detail the technical or mechanical process of cleaning carpet. This process involves following the steps set forth in S100, the Standard and Reference Guide for Carpet Cleaning as set forth by the Institute of Inspection, Cleaning, and Restoration Certification (IICRC). Those steps are:
- Dry Soil Removal
- Soil Suspension
- Suspended Soil Removal
- Finishing or Grooming
In previous conversations, we discussed the absolute importance of thorough soil suspension. As we move into the next step, suspended soil removal, it must be understood that the success of the soil removal step is directly proportion to the degree of soil suspension. This month I want to address the soil removal process as it is used in the hot-water extraction process. This is the most widely used process, particularly with residential cleaning.
Remember, we, as technicians, serve in the role of the cleaning machine. We have to facilitate the dry soil removal by vacuuming, the fluid soil suspension using TACT (Temperature, Agitation, Chemical Action, Time) and then the suspended soil removal. With hot-water extraction, the soil removal process is accomplished by rinsing. The rinsing is done with a light wand or with one of the various mechanical tools available to facilitate the rinsing process. The key is to thoroughly rinse the totally suspended soil. We need to constantly be appraising the whole process, checking the five steps listed above as to the maximizing of their role in the cleaning process. When I teach a Carpet Cleaning Certification (CCT) class, I’ll have the students demonstrate their use of the light wand. Everyone develops their own specific technique over time. One thing that I try to emphasize is that the handle on the wand is to help place the wand. It is not to lean on to help add force to the extraction. The weight of the wand itself is sufficient to facilitate rinsing. The addition of the various composite vacuum shoe attachments has added to the rinsing efficiency.
How many passes are needed to remove the suspended soil? In light soil areas, often only a single wet pass is sufficient. In heavier soiled areas, usually double wet passes are required. In the most impacted areas, such as entries, concentrated chop stoking may be warranted, or just multiple wet strokes.
In surveying many cleaners, most will use about 400 psi with the process. Higher pressures will deposit more water on the carpet and thus will require more dry stroking. Typically, cleaners who use a mechanical extraction tool will reduce the pressure in accordance with the manufacturer’s recommendation.
The second part of rinsing is the instant vacuuming with the wand or tool. The wet vacuuming is instant with the application of the rinse solution. Dry stroking is very important to remove as much of the rinse solution as possible. This step is tantamount to the spin process with a clothes washer. The spin step in washing clothes is important to remove all the water the fabric will release, thus making drying easier. As we clean a carpet, we want to leave the carpet as dry as possible, thus shortening the length of time that it takes for the carpet to fully dry. The fifth step in the cleaning process, drying, will be discussed in length in a later issue, but suffice it to say that if the carpet is taking longer than six to eight hours to dry, it may be that we did not do a good job in the “spin” process.
Next month we’ll discuss the soil removal process associated with other cleaning methods.
Bulletin Board Material
“The years teach much that the days never know.” In other words, there is no substitute for experience.