Bill Luallen

Bill Luallen is the Director of Technical Services for XL North, a division of Textile Rubber and Chemical Company. He is the current IICRC CCMT TAC Chair and also the former Vice Chair of the RFMT. He participates on many panels and boards including the CRI 204/205 Carpet Maintenance and Cleaning Standards. When Bill is not traveling to work with customers or talking on the phone, he spends all his down time with his wife Cynthia of 30 years, outside enjoying this beautiful world.


An epidemic has started in the world of flooring and, unfortunately in some cases, it cannot be corrected. It’s not done maliciously and it starts before anyone realizes it. In this new world of “sanitize this and disinfect that”, facility staff is asked or told to include flooring in the disinfection process. It’s at the heart of a flooring epidemic known as quaternary yellowing and quaternary walk off.

At XL North we began seeing this problem in healthcare environments. The goal of these facilities is to maintain a high level of sanitization, but unfortunately the chemistry used and how it works is typically not understood. Quaternary ammonium compounds (quaternary disinfectant detergents) are the most popular of all disinfectants on the market. These products are acceptable for use on most flooring when used with proper dilution ratios and procedures. However, what we’ve found in the field, is the most important step in flooring maintenance – a proper rinse of the floor before reopening the space – is often overlooked. The outcome is quat yellowing and it can be fatal for flooring. It happens on all types of resilient flooring and its finishes, from VCT to sheet vinyl, from rubber flooring to linoleum floors.

Here, our pH paper indicates the residue on the flooring is sitting at around 10-11 pH. As manufactured, the flooring itself is neutral.

Quat yellowing doesn’t only happen when mopping. It can also happen with spray quaternary disinfectants. Here’s an example where repeated overspray of a disinfectant came in contact with a vinyl floor and was not properly removed. Not only damaging to floors, it can affect topical finishes applied to flooring by softening or yellowing them, and when not addressed in a timely manner, can then yellow the flooring material as well.

Often asked how to “fix” the yellowing that can occur, we’re trying to create a correction process for the issue and, frankly, we have had mixed results at best. Typically we have to go outside of the manufacturer’s recommendations for cleaning to achieve results, which are dependent on the severity of the yellowing and the type of flooring material.

A second issue we see from using quaternary disinfectants on flooring is the effect on nylon carpet. Here’s a typical maintenance scenario: a service provider cleans restroom tile flooring with a product containing ammonium chloride disinfectant. After mopping, it’s left to dry because often the label states “No rinse needed”. The chemistry on the floor, a cleaning solution with a disinfectant, is doing its job. The surfactant portion of the chemistry is attracting the soils and creating micelles around them. These don’t disappear or evaporate; they remain on the surface and wait to be removed. Once foot traffic in and out of the restroom resumes, this residue clings to the soles of shoes and is transferred to carpeted areas. It’s the start of a serious problem that we call quaternary walk off. The chemical reaction that causes this issue is known as reverse saponification.

Reverse saponification is when a quaternary surfactant (cationic charged (+)) and standard carpet cleaning chemistries (either non-anionic or anionic charged (-) ) come in contact with each other. These opposite electrical charges (which if you think of having two magnets and allowing the “positive” end to connect with the “negative”, it’s really hard to pull apart) create a situation that has only one corrective procedure – the attraction of the two opposite charges has to be dispersed or neutralized before attempting cleaning. We use chemistry, such as GRAB Charge Away, to dissipate the charge so that normal cleaning chemistries and procedures can then be used to finish the job. In most cases, the situation can be corrected.

When it comes to disinfection, people are doing what they think is right. Consider this quote, however, from the CDC’s (Centers for Disease Control and Prevention) “Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008. “In an investigation of the cleaning of a hospital floors … a few hours after floor disinfection, the bacterial count was nearly back to the pretreatment level.”

In my opinion, and for the record I’m not a chemist, quat yellowing and quat walk off can be prevented with one additional step – rinsing the floor. And while some will say, “It takes too long,” “We can’t afford it,” or “It’s not in the contract,” prevention is always easier, cheaper, and a better use of time and resources than trying to find a cure.