High Performance Cleaning Promotes Good Hygiene and Health Part 1

Health issues and microbiology-based cleaning concerns are rising. Anthrax, HIV, mold, the West Nile Virus and the more recent Avian or Bird Flu make understanding what we are confronting critical. Without that understanding, our ability to solve problems and protect clients, cleaning professionals and ourselves becomes limited.

First we must recognize that:

  • Knowledge of our micro-biological world is incomplete due to its unpredictable environment;
  • Cleaning alone does not always quell epidemics; and
  • Historically, effective cleaning successfully removed biological hazards and created conditions that reduced the risk of disease and enhanced man’s longevity and quality of life.

The following overview will help cleaning industry members approach these issues in a systematic and science-based manner.

The Science Behind Cleaning
Clean means being free of unwanted matter. Cleaning is what puts that unwanted matter in its proper place. Doing so prevents it from disrupting our activities or harming individuals and their valuables. Cleaning also reduces health risk exposure.

Science is essential to effective cleaning. It answers the question of “how:” “How does our environment function?” and “How is cleaning effective?”

Every effective cleaning process, especially as it applies to protecting our health and environment, requires:

  • Knowing the environment and the matter to be removed;
  • Separating, isolating and containing unwanted substances;
  • Transporting and removing the substance; and
  • Properly relocating, repositioning or disposing the unwanted substance.

Science claims that an environment is a system of interconnected compartments and sub-compartments through which matter and energy flow. Matter and energy are never destroyed but rather are in constant motion. Without effective cleaning, unwanted matter collects and concentrates, particularly in built environments. Various forms of out-of-place matter cause a multitude of adverse health effects and conditions.

Pathogens Produce Disease
Unwanted matter is often referred to as a pollutant or pathogen. It can be a solid, liquid or gas; organic or inorganic; living, dead or derived from a living or dead organism. Biopathogens are pathogenic microorganisms or substances derived from living, disease-causing organisms.

A germ is a microscopic organism that takes in food and excretes waste, grows, reproduces and dies. Germs are bacteria, viruses, fungi and protozoa.

Bacteria are single-celled organisms that survive on nutrients from their environments, such as a human body. Bacteria cause infection and therefore can reproduce outside or inside our bodies. Not all bacteria or microorganisms, however, are harmful. Some are essential to our well-being.

Bacteria are prokaryotes meaning their genetic material (DNA) is not enclosed in a nucleus. Other life forms, including plants, animals and fungi, are eukaryotes or creatures with nuclei. Viruses are not considered cells and are a separate category of living organism.

Bacteria live on or in virtually every material and environment. A square centimeter of skin averages about 100,000 bacteria. A cubic centimeter of topsoil contains around one billion bacteria. Bacteria live in temperatures above water’s boiling point and in those that freeze blood. They “eat” everything from sugar and starch derived through photosynthesis to sulfur and iron in rocks.

Protozoa are one-celled organisms like bacteria. They require—and thrive in—water, often spreading diseases through contaminated water. Some protozoa cause intestinal infections that lead to diarrhea, nausea and stomach pain.

Fungi are multi-celled, plant-like organisms that do not produce their own food from soil, water and air. Instead, they are decomposers whose main function is recycling carbon, which, along with water, is essential to all life. Fungi thrive in damp, warm environments and get nutrition from plants, animals and most matter derived through photosynthesis.

Viruses cannot live outside other living cells. They require a host for survival, growth and reproduction. Once inside the body, viruses can spread and cause illness, such as chickenpox, measles and the flu.

Hygiene Prevents Disease
Germ theory is the foundation of most hygienic and sanitation practices. The 180-year-old “germ theory of disease” (“pathogenic theory of medicine”) proposes that microorganisms cause many diseases.
Hygiene prevents disease and infection through cleaning. Good hygiene results in no visible soil, malodors or harmful bacteria levels, microorganisms or harmful matter. As with cleanliness, good hygiene enhances health, aesthetics, comfort, social interactions and productivity. During an epidemic good personal hygiene and effective cleaning reduces contagiousness.

Washing with water is the most common form of personal hygiene. Washing with soap or detergent separates oils and breaks up dirt particles allowing them to be carried away by water. Hand washing and effective cleaning greatly reduce the spread of disease because disease-causing organisms in the immediate surroundings are killed or removed. These cleaning processes reduce pathogen exposure and lower the risk of disease. For example, washing your hands after using a bathroom or restroom and before handling food reduces the chance of spreading E. coli bacteria and Hepatitis. Both diseases spread from fecal food contamination. Hand washing also reduces the spread of the common cold virus and various forms of influenza, especially in sensitive environments like hospitals, nursing homes, daycare facilities, schools and universities.

Isolating infectious organisms is the primary method of preventing the spread of disease. Removing the infection source also eliminates transfer, exposure and risk. Effective cleaning often provides this isolation and risk reduction.

Michael D. Berry, Ph.D., was chairman of the Science Advisory Council for the Cleaning Industry Research Institute (CIRI) in 2006. The information contained in this article was extracted from Dr. Berry’s papers and presentations at CIRI’s 2007 Cleaning Science Conference and Symposium. His entire paper and Power Point presentation, as well as those of other symposium presenters, are available at www.ciri-research.org.


Published with permission by the Cleaning Industry Research Institute © 2008.



Michael A. Berry, PhD serves on the Science Advisory Council of the Cleaning Industry Research Institute (CIRI).


Dr. Michael A. Berry retired from the US Environmental Protection Agency in 1998 after a 28 year career with that agency. In EPA he was a senior manager and scientist. He was the Deputy Director of National Center for Environmental Assessment at Research Triangle Park, NC for 22 years. During his EPA career, he had extensive interactions with private industry, trade associations, environmental organizations, governments, the federal courts, US Congress, universities world-wide, and institutions such as the National Academy of Sciences, the World Health Organization, and the North Atlantic Treaty Organization. Dr Berry is recognized internationally as an expert in the subject of indoor environmental quality. Between 1985 and 1994, he directed EPA's indoor air research program.

Since his retirement from EPA he has been a Research Professor at the University of North Carolina at Chapel Hill where he taught several course and wrote numerous articles related to business and environment, built environments, and environmental science and management. He serves as a consultant to businesses and public institutions in the evaluation of environmental management strategies and policy. He directs research on the performance of products and services related to indoor environmental quality. Currently his research focus is the area of cleaning science and indoor environmental management programs for schools and universities.

Dr. Berry served as an Army Officer in Viet Nam 1967-68. He earned a Doctor of Philosophy in Public Health from the University of North Carolina at Chapel Hill, and a Master of Science in Management from Duke University's Fuqua School of Business. He holds both Bachelor and Master of Science degrees in Mathematics from Gonzaga University.