cut & pasted this from the ICS site
On the front page of the June 2009 Bane-Clene newsletter is an article with the title "Pre-Vacuuming required for all cleaning?"
In the article, Bill Bane makes the argument that the CRI (and I suppose, the IICRC) is in error for requiring that carpets be prevacuumed prior to cleaning.
"Vacuuming carpet, especially with an agitation device, stirs up dry soil and dispenses dust particles into the air. Hepa filter sales have increased thanks to the hyperbole about vacuuming. But the fact is tha most portable vacuums dispense dirty, rancid air back into the room atmosphere."
Mr Bane then goes on the explain that "Bane-Clene's ExternalExtraction with a gentle cleaning agent, wets the soil keeping it from becoming airborne. Moisture and soil are simultaneously extracted and exhausted through a sealed hose along with foul air to the outside of the building where it dissipates into the atmosphere. The results are faster drying carpet, minimal residue and a lingering clean fragrance."
What he seems to be saying is hwe, when properly performed, does not need prevacuuming. HWE will extract the soils by itself, and prevacuuming carpets, even with Hepa filtered vacuums, exposes the indoor environment to allergins and contaminants.
Do you agree or disagree with Mr. Bane?