How To Clean Carpets Using Chemicals

When asked how to clean carpets, jan/san distributors overwhelming agree that a thorough vacuuming is essential. Once carpets have been vacuumed, it’s on to step two. Distributors recommend that janitors prespray carpets to help loosen soils that vacuuming alone cannot recover. A good prespray not only improves the effectiveness of carpet extraction chemicals but also addresses issues of chemical buildup.

Kevin Harris, president of Aspen Maintenance Supply in Basalt, Colo., encourages custodial experts to mix their extraction shampoo in a pump-up sprayer, prespray the carpet and then allow the chemical to dwell on the carpet. While a dwell time of five to 10 minutes is standard, Harris recommends a dwell time of three to five minutes in areas where evaporation rates are high.

“That’s really the key component of the chemical,” he says. “Allow it enough time to actually work on the carpet, then just run clean water through the extraction machine and flush it all back up. We’ve found that to be very effective to avoid resoiling due to residue left in the carpet.”

Indeed, resoiling due to residual chemicals left behind in the carpet is one of the major challenges of extraction. Most extraction shampoos are alkaline in nature, and although alkaline detergents suspend soil well, they also tend to leave behind residue. Every time the carpet is cleaned, that alkaline is reactivated, causing the carpet to resoil more quickly or become dull and stiff.

“Prespraying is important when you have heavily soiled carpets or carpets where you’ve got too much chemical in them to begin with,” says Tom Murphy, sales manager for RoVic Inc., Manchester, Conn. “If you use too much shampoo or extraction cleaner over a period of time, it builds up in the carpet.”

To neutralize the alkalinity in a carpet, he suggests using an acid rinse.

“In our experience most commercial carpets have an awful lot of buildup in them. Before we can get them clean, we have to rinse them thoroughly with a mild acid prespray to take out the heavy alkaline substances we’ve been using to clean it previously,” Murphy explains. “Then to rinse the carpet, we would use the tank of the machine itself.”

KASSANDRA KANIA is a freelance writer based in Charlotte, N.C.