There are three concepts frequently mixed up in literature and online articles, especially those related to the COVID-19 preventative measures: decontamination, disinfection, and sterilization. In this article, we want to dot the i’s and cross the t’s with these concepts and explain their core differences and applications.

Definitions

Decontamination is the broadest definition of all three in terms of goals and procedures. This is the process of removing undesirable elements from an object or area, such as microorganisms, chemicals, and radioactive substances.

Disinfection is the process of minimizing or completely eliminating many or all pathogenic (harmful) microorganisms, except bacterial spores, on inanimate objects and surfaces. Low-level disinfection solutions kill most vegetative bacteria, some viruses, and fungi relatively fast, while high-level options might even be hazardous for people.

Sterilization is the process during which all kinds of living microorganisms, including viruses and spores, are removed from a surface or inanimate object.

As you can see, decontamination includes in its core both disinfection and sterilization, but the latter two have a significant difference. After disinfection, some particles may remain, while after sterilization, the surfaces get absolutely clean from all living organisms. This is why disinfection solutions are used for COVID-19 preventative measures while sterilization is applied in surgical wards, for instance.

Types of Sterilization and Disinfection Solutions

Disinfection comes in a wide range of methods, where the chemical one is the most common. The type of disinfectant in use depends on the kind of microorganisms you need to eliminate and which surfaces undergo decontamination. For example, a disinfection solution for body must be significantly less aggressive than a disinfectant in the hospital. Here are the top types:

  1. Quaternary Ammonium Compounds (Quats): These are low-cost and most effective disinfectors (also used against SARS-CoV-2).
  2. Chlorine Compounds: Inexpensive and effective but may cause corrosion and irritation. In low dosages suitable for use on humans and during food preparation processing.
  3. Alcohols: These are effective against bacteria (but not always against organic matter) and are frequently used for wet surface disinfection.
  4. Aldehydes: Such disinfection solutions are perfect against Tuberculosis bacteria yet usually leave a greasy residue and may cause asthma.
  5. Iodophors: Commonly used for non-critical medical equipment disinfection but have an unpleasant odor and may leave stains.
  6. Phenolic Compounds: Very effective against fungi and viruses, but they are toxic and corrosive. Specific disposal restrictions might apply.
  7. Hydrogen Peroxide: This is the most sustainable solution suitable for humans.

Disinfection also may come in a gas or liquid (dispersed) form. It is commonly used in disinfection tunnels (if you are interested in disinfection tunnel chemical composition, read more about this solution in this article).

Sterilization, as well as disinfection, is used not only in medical facilities or the healthcare sphere; it is also a common element of the beauty industry where instruments for manicure and facial treatments also have to undergo sterilization before use. Here are the top types of sterilization.

  • Steam (autoclave): fast and efficient sterilization (5-10 minutes under 258-280°F) that inactivates all fungi, viruses, bacteria, and bacterial spores.
  • Dry-heat sterilization: requires higher temperatures and longer exposure time (30-180 minutes for 320-356°F); effective for powders and items that bear high heat.
  • Filtration: effective for thermolabile solutions; they need to go through several stages of filters for the complete cycle.
  • Ionizing radiation: used for drug products and medical devices as well as their final containers. Being a radioactive process, it is hazardous and so requires highly-trained specialists.
  • Gas sterilization: ethylene oxide and other highly volatile substances are used for this method. It is excellent for packaging and all sorts of smaller objects, yet it is a complicated process rarely used in everyday practices.
  • Chemicals: Ozone, Aldehydes, Hydrogen Peroxide, and many other disinfection solutions can be used for complete sterilization but with higher dosages.

The Difference between Disinfection and Sterilization

The difference between these two methods comes from the underlying need to clean a particular surface or object. Generally, Spaulding’s approach to sterilization and disinfection solutions has been popular in the healthcare industry for more than 35 years. It clearly defines which items should be sterilized and which ones need specific disinfection. Today, however, the need for both procedures has increased with the development of the COVID-19 pandemic.

The core distinction lies in the need to kill all or particular microorganisms from a surface. For example, objects that have direct contact with humans and living beings, their bodies, and internal organs must be sterile while the surroundings can be disinfected only to some extent. To fight the deadly virus and make the environment disinfected of the COVID-19, many institutions (not only healthcare ones) started using sanitation disinfection tunnel kit solutions at the entrances, introduced disinfection gels, and also increased monitoring measures to control the disease spreading. 

Disinfection and Sterilization in Daily Life

In everyday life, sterilization is never used. These are specific healthcare-, food-, and beauty-related procedures that have to be taken due to a set of regulations for every industry to prevent severe infection of living beings. Disinfection, on the other hand, is an ordinary daily routine for many businesses and even households these days. The fast-spreading of COVID-19 changed the way people clean their homes and belongings. Today, Centers for Disease Control and Prevention inform people on how to disinfect their electronics and sofas; governments begin installing sanitation disinfection tunnel kit solutions, while all businesses (restaurants, stores, entertainment locations, etc.) apply disinfection solutions to all their publicly-accessed spaces in the fight for healthy peoples. Furthermore, individuals even carry their own disinfection solutions for hands (check here to ensure that your hand sanitizer meets state regulations and is effective against the virus), special wet wipes for the surrounding objects (to minimize the number of microorganisms around them and better control their own health). 

The Bottom Line

Disinfection and sterilization both have the same aim – to remove undesirable microorganisms from surfaces and spaces. The core difference lies in the types and number of those being removed. While disinfection solutions target specific pathogens and are impotent against bacterial spores, sterilization procedures guarantee perfect decontamination of a space or objects. The former are frequently applied in every person’s and industry’s daily life, whereas the latter is closely connected to the healthcare, food, and pharmaceutics fields and businesses.