Quaternary Ammonium Compounds (QACs or quats) are often used to kill microorganisms in food production, food service, health care, and other environments. Their flexibility of application, residual efficacy, and mild odor make them an attractive choice when picking a disinfectant. Recently, subinhibitory levels of QACs have been shown to lead to microorganisms that are resistant to this biocide called superbugs (see the article from August here).

DeVere offers a wide range of cleaners, sanitizers, and disinfectants. Some of these contain QACs. This post will help clear up any confusion regarding when and when not to use them.

When to use QACs

Improper use of QACs can lead to superbugs. Proper use can make them one of the most efficient tools available in our war against pathogens. Generally, QACs can be used to disinfect flat, hard surfaces where the product will not end up in a drain or on the floor. For example, they work well when sanitizing desks, tables, food processing surfaces, and windowsills (primarily for mold inhibition).

QACs also work well as sanitizers in the 3rd sink in bars and other foodservice areas with 3-sink setups. 3rd sink applications will eventually send the QAC to the drain undiluted. The undiluted part is the key. The idea here is that they do not last long in a subinhibitory concentration before other materials in the sewer or septic system deactivate them.

One Step Quaternary Cleaner and Disinfectant and QDII Sanitizer are two of DeVere’s QAC-based products and are often used when sanitizing and disinfecting flat surfaces. See their product pages for more details on the product and when to use them.

QACs are generally not great cleaners on their own, but many of our products that contain them are great cleaners. Products like Restroom Cleaner and Deodorizer contain QACs to help deodorize and make surfaces safe for human use.

When not to use QACs

If you plan on sanitizing or disinfecting entryways, floors, or drains, we do not recommend QACs. This includes quat rings, door foamers, powdered quat, and any other application where the product will be slowly diluted while exposed to pathogens. Much like they can evolve immunity to antibiotics, bacteria and viruses can evolve resistances to QACs. The resistances are formed when there is not enough QAC present to kill pathogens and enough to react. See this article for references and more information.

Security Floor Treatment and Security Floor Sanitizer are DeVere’s top alternatives to QACs and use oxidizers as primary active ingredients. Pathogens cannot build resistance to oxidizers. This means that these products are perfect for use on floors and around drains. To learn more about each product, you can visit their product pages, and see this post to learn about the differences between each product.