from NCCA Newslink Feb 2004
Why dry vacuum? By Robert Olifent
Can I save time by not vacuuming?
Should we always dry vacuum?
There are generally two 'main types' of soil that carpet cleaners need to consider when cleaning carpets and soft furnishings.
1. Dry particulate soil (loose) i.e. sand/grit, dust, soil.
2. Oily greasy soil (bonded)
It has been suggested that in the region of 90% of soiling held within carpet is of the dry particulate dust/grit type soiling. This particulate soil can generally be more effectively removed by a thorough dry vacuuming. If a fully soil laden carpet is wet without dry vacuuming this dry soil becomes a slurry making it far more difficult to remove by wet means. This will often necessitate more wet passes with the floor wand, creating wetter carpets, longer drying and the propensity for wick back and other associated problems of over wetting. So you decide, is it quicker to cut out the pre-vacuum?
Are there instances where it is not necessary to pre-vacuum?
Well this is where the inexact science comes into play, and some would say always vacuum and others would say yes but what if!
As a general rule vacuuming should be carried out religiously, however if a cleaner were faced with a grease-laden carpet in a Chinese restaurant, in my view it would be a total waste of time and effort in pre- vacuuming. Like wise with a pub carpet that is so thickly built up with soil that it is as hard as wood and you cannot see the fibres underneath. This is bonded soil that cannot be dry vacuumed out! All that you will do is to soil up the brushes on you vacuum cleaner unnecessarily, with no benefit to the carpets cleanability. In my opinion the only way of cost effectively dealing with such a degree of soiling is providing a restorative clean by wet means.
Areas to particularly concentrate the vacuuming are obviously within the main walkways at the ground floor areas adjacent to the outer doorways. Learn to give more effort to these main traffic ways and less effort to the underneath of furnishings where clearly there will be less dry particulate soiling to contend with.
Generally the main soiling that our customers are unable to deal with is that of bonded greasy/oily type soils and staining. This soiling may be deposited from airborne descending cooking vapours, foot trafficked Tar, grease spillages, gum, oils from pet fur, carbon within the atmosphere, body fats, filtration draft marks, etc. etc. These are soils that cannot be readily removed with standard dry vacuuming systems.
So I would have to say that generally it is common sense, by concentrating efforts on the pre-vacuuming (particularly within the main traffic areas) will make the job easier, safer, and leave carpets drier, and what we all want, a happy customer.
Regards
Robert Olifent