The Difference Between Cleaning, Sanitization, and Disinfection
Our eyes can trick us into thinking something is clean when it really isn’t. Bacteria and other microorganisms stay behind even when we’ve wiped down a surface. And it only takes one touch to both deposit and pick up more germs and transport them to new places. So when a surface is soiled what is truly clean? And what is the difference between cleaning, sanitizing and disinfecting a surface? Read on and learn!
Cleaning is the removal of soil from a surface, so we first need to understand typical soil types. Soil is broken down into three categories:
- Organics such as fat, grease, and living matter such as mold, yeast and bacteria;
- Inorganics such as rust, scale and mineral deposits most commonly sand, silts and clays;
- Lastly and most difficult to clean is when a combination of organic and inorganic soil is present.
To understand the process of cleaning, a basic chemistry lesson is in order. Let’s start with the distinction of surfactants. Surfactant is short for Surface Active Agent, and they are chemicals that are dissolved in water or other solvent bases that aid in the cleaning process. To keep things simple, at a molecular level, surfactants are on one end attracted to dirts, oils, and grease, and on the other end they are attracted to water. Because of these polar attractions, surfactants surround soil particles, dislodge them, and suspend them in water allowing them to be effectively cleaned from a surface. The diagram below shows the process.
In addition to surfactants, cleaning products blend a variety of solvents with surfactants to optimize cleaning of organic, non-organic and soil combinations. These include water, alcohol, butyl and limonene to liquefy and dissolve soil into small particles so the surfactants can do their job. Cleaning is an important step in creating a surface environment conducive to sanitizing and disinfecting.
While the cleaning process may remove some bacterial matter from a surface, it does not include antibacterial products designed to significantly reduce the presence of bacterial colonies. Sanitization is the killing of bacteria by 99.9 percent, which is generally considered a safe or non-threatening level. Sanitization methods can be categorized into the two common categories of chemical and radiation (UV light). Common chemical sanitizers are chlorine, iodine and peroxide. These chemicals also react with organic matter, so will be less effective when a surface has not been cleaned. Soiled surfaces also shade microorganisms from UV light, making radiation less effective. This is why effective cleaning processes play an important role in effective sanitization. Sanitization does not address virus and fungus spores and illnesses caused by them. See below for more on that.
Disinfecting a surface is the killing of all bacteria, viral and fungal pathogens by 99.9999 percent. Dwell, exposure or contact time is a critical variable in the utilization of chemical, radiation, and heat-based disinfecting methods. As such, certain dwell or exposure times must be met in order to ensure a surface has been successfully disinfected. Much like sanitizing, effective cleaning plays an important role in effective disinfection of a surface.
In practice, how should managers in various roles move forward effectively with this knowledge? Because managing labor costs is a big element of almost every service or product industry, be it education, business, government, law enforcement and of course healthcare, it is a meaningful basis to approach application of these methods. Low-risk surfaces such as floors, windows, etc. are appropriate candidates for standard cleaning protocols because the likelihood of pathogen transfer from the surface is low. Shared human contact surfaces such as door handles, railings, and shared work surfaces where pathogen transfer can occur between users are appropriate candidates for cleaning and sanitizing protocols. Where labor costs are a concern, new passive sanitizing technologies such as hand sanitizer stations, SafeHandles products, and UV stations are low-labor, cost-effective means to sanitize these surfaces. Food contact surfaces and certain healthcare environments required rigorous cleaning, sanitizing and disinfecting protocols that use the above technologies as well UV-electroclave and autoclave methodologies.