The Difference Between Disinfection, Sanitization and Cleaning

Cleaning spray bottle02.26.2015

Written by: Selective Micro Technologies

When looking for a product to “clean” your home, office, clinic, nursing home, or whatever environment you are trying to freshen up, it is important to know the differences between technical terms presented within the janitorial and infection prevention industries. Below is a discussion regarding these differences in order to support awareness and decision-making capability.


The term “disinfection” is often confused and misused in the infection prevention industry. Many times, it is used interchangeably for cleaning, sanitizing, sterilizing, etc. However, there is quite the difference between disinfection and sanitization. For example, according to the United States Environmental Protection Agency, a disinfectant is “A chemical or physical process that kills pathogenic organisms in water, air, or on surfaces.” The EPA must approve any product claiming to be a disinfectant by accepting submitted efficacy data, or proof of the products ability to kill microbes.

The EPA further classifies disinfectants into three groups, which are based upon data submitted: limited, general (or broad spectrum) and hospital disinfectant. A limited disinfect is registered for use against a specific grouping of microorganism, a general/broad spectrum disinfectant is registered for use against gram positive and negative microorganisms, and a hospital disinfectant is a registered broad spectrum disinfectant that can also kill Pseudomonas aeruginosa. Any type of disinfectant must achieve at least a six log reduction, or 99.9999% of its specific microbes.


“Sanitization” is another term which can be a bit confusing. It can often be confused with “sanitation,” which refers to the treatment and safe handling of human waste. The EPA defines a sanitizer as “an antimicrobial that reduces but does not necessarily eliminate all the microorganisms on a treated surface.” To be classified as a sanitizer, a product only needs to demonstrate a three log (or 99.9%) reduction of bacteria.

As you can see, there is quite a difference in total reduction of microbes between the two. When considering percentage alone, it may not seem like much of a difference, but consider the following: If a 10” x 10’’ surface contains 1o,000,000 colony forming units of bacteria, a 99.9% reduction would take that number down to 10,000 cfu/bacteria. While that is quite a reduction, a 99.999% kill rate would leave you with only 100 cfu/bacteria.


The term “clean” is a little grayer than the previous two. According to the EPA, cleaning is “the process of removing unwanted substances and putting them in their proper place.” By this definition, cleaning could encompass both disinfection and sanitization. However, cleaning is also generally understood as the removal of any debris--organic or otherwise--from a surface. Cleaning typically precedes any sort of sanitization or disinfection. This removal of debris provides some sort of microbial reduction, but it is not significant or largely supported by scientific data.