Cleaning Creates a Healthy Condition

Cleaning’s primary objective is creating a condition of well-being for individuals. To that end, the process of cleaning lowers adverse exposure levels and risks by removing unwanted substances from the environment.

The quality of our lives largely depends on how effectively we manage our immediate habitat. Man’s intrinsic connection to his environment creates a constant demand for healthy, life-sustaining surroundings. The quality of those surroundings, in turn, affects the quality of human life. Our thoughts of the environment are primarily on a global, regional or local level, as it exists outside in nature. This outside space is the ambient environment. The built environment, however, is man’s primary human habitat. A sub-compartment of the ambient environment, the built environment is the one to which man is exposed more than 90 percent of the time.[1] It also is the environment that most influences the quality of human life and health and the one over which we have the most control.

The Healthy Human Condition


For most of recorded history, the healthy human condition simply meant being alive. As recently as 60 years ago, chronic sickness and death before the age of 50 was the average for most of the world.[2] In more recent decades,[3] medical and health sciences have extended normal life expectancies beyond 75 years.[4] This has been achieved through educational improvements; early detection and treatment of common diseases; access to a variety of foods and improved diets; and changes in social attitudes and personal behaviors. The measurable improvements in environmental conditions as a result of good hygiene and cleaning practices have made the greatest impact.

Human health is the primary environmental concern. One of the important factors surfacing lately is our broad definition of health. The World Health Organization’s (WHO) definition goes beyond traditional concerns for visible disease. It forces us to recognize that an individual’s health includes a sense of security and well-being, both of which are strongly linked to a perception of the environment. According to the WHO, “Health is the state of complete physical, mental and social well-being and not merely the absence of disease and infirmity.”[5]

Around the world, environmental health concerns represent a powerful sense of destiny that should not be ignored. The environment is a value worth protecting and keeping clean. It is recognized that poverty, malnutrition, unemployment, population growth, lack of heath care and pollution are interrelated. The elevated quality of human existence also requires a clean environment in which wealth can be created.

Cleaning is instrumental in preventing most diseases. It is a well-known public health fact that the vast majority of diseases worldwide relates to filth and can greatly be reduced by sanitation and cleaning practices.[6] As populations grow and mobilize, it is critical that wastes be managed through cleaning. If not, those wastes will inhibit productive enterprise and cause unnecessary human suffering.[7]


Two Parts to Human Health


Human health is physiological and psychological. The aspects of both are significantly determined or influenced by environmental conditions and man’s exposure to those conditions. The physiological aspect usually is associated with health and is freedom from common disease and physical infirmity. The psychological aspect is an elevated sense of “well-being” that puts us beyond physical discomfort, mental anxiety and a sense of fear and hopelessness. To a large extent, good health is a positive state of mind that translates into happiness and productivity.

The immediate environment also affects mental health through the attitudes and feelings of those residing within that environment. Attitudes affect behaviors and behaviors, in turn, determine positive or negative actions and outcomes. When our immediate environment is viewed as clean, safe and ordered, we feel better. Conversely, when our environment is perceived as hazardous to our health or as being somehow annoying and stressful, we are not at our best. Anything that contributes to that negative feeling makes us feel unhealthy.[8]

Much of a building’s “healthy” condition depends on how it looks and feels. Generally, this is determined by the degree to which it is cleaned. Cleaning cannot be separated from building design. Buildings that are not designed and constructed for easy and effective maintenance eventually deteriorate to an oppressive state rather than one that enhances the quality of life.

Essential elements for an indoor environment’s high performance must at least address the following, each of which somehow depends on effective cleaning.

  • Usable clean space that is made possible by cleaning and promotes social interaction and productivity;
  • Safety, such as preventing slips, falls and toxic exposures, which is enhanced by cleaning;
  • Aesthetics or a beautiful view created by cleaning;
  • Physical comfort provided by cleaning;
  • Lighting that includes managing glare or reflecting light and is enhanced by cleaning; and
  • A sanitary environment provided by cleaning.[9]

Breaking the Transmission Chain of Infectious Agents


Effective cleaning is at the core of the Sanitation Revolution. That revolution did more to extend life expectancy than any other event in history. The 180-year-old germ theory of disease—also referred to as the pathogenic theory of medicine—proposes that microorganisms cause many diseases.[10] Germ theory is the foundation of most areas in the health profession that include hygienic and sanitation practices.[11]

Hygiene is commonly understood as preventing disease and infection through cleaning. In cases of good hygiene there is no visible soil, malodors or harmful levels of bacteria or other microorganisms. As indicated by a state of cleanliness, good hygiene also creates a sense of well-being and enhances health, aesthetics, comfort, social interaction and productivity. Frequently, the process of high performance cleaning directly aids in preventing disease and isolation. Additionally, good hygiene—as manifested by cleanliness—maintains a healthy condition and avoids sickness and disease. During an epidemic, good personal hygiene and effective cleaning processes reduce contagiousness.

Isolating the infectious organism from the population is the primary method to prevent the disease from spreading. Eliminating the source of infection breaks the transmission chain and there is no transfer, exposure or danger. Effective cleaning often provides this isolation and reduces risk.


Common Infectious Diseases and Transmission Routes

Direct Contact





Cold Sores


Head Lice





Common Cold


Bacterial meningitis

Hand-Foot-Mouth Disease









E. Coli O157



Hand-Foot-Mouth Disease

Hepatitis A

Infectious Diarrhea






Hepatitis B

Hepatitis C

HIV Infection

Direct contact-related diseases are best managed by isolation. Skin infections are transmitted by touching fluid from another person’s infected sores. Effective cleaning takes place through personal hygiene on the part of the infected individual to contain, destroy, remove or inhibit the life of the bio-pathogenic organism or its toxic by-products.

Respiratory tract infections, evidenced by coughing, sneezing and a runny nose, are spread through exposure to fluids present in, or expelled from, another person’s saliva or mucus. These infections often occur when an uninfected person touches these discharges and subsequently touches their mouth, eyes or nose. The organisms tend to be viruses that do not survive long absent a living host. Personal hygiene, especially frequent hand washing, reduces fluid exposure. Rapid response in the form of effectively cleaning surfaces contaminated by virus-active fluids also breaks the transmission chain and reduces transfer opportunities and risks.


Intestinal tract infections, such as diarrhea, spread through exposure to bacteria in feces. Bacteria are spread by “fecal-oral” transmission. Pathogenic organisms are excreted from the infected individual and enter another’s body orally. This occurs when objects contaminated with undetectable amounts of human or animal feces are placed in the mouth.

Fecal-oral transmission occurs if food or water contaminated with undetectable amounts of feces is ingested. Improperly prepared foods made from animals (meat, milk and eggs) often are the source of infection with Campylobacter, E. coli O157.H7 and Salmonella. Well-designed and focused cleaning systems and programs are effective in reducing—and often eliminating—these types of diseases. Infections, such as Salmonella and Campylobacter, spread through direct exposure to infected animals. Isolating these animals, hand washing and frequently cleaning animal holding areas reduce risk.


Preventing Sick Building Syndrome


Unclean buildings come with health complaints, hence the term “sick building.” Such a term evokes an image of what occurs within an indoor environment when occupants complain of occupancy-related health and comfort problems. The truth is there are no “sick buildings,” only mismanaged ones that often are inadequately cleaned.

Health effects commonly associated with inadequately cleaned buildings include:

  • Eyes, nose and throat irritation associated with pain, dryness, stinging, hoarseness and voice problems;
  • Skin irritation that manifests itself as pain, reddening, smarting, itchy and/or dry skin;
  • Neurotoxic symptoms associated with headache, sluggishness, mental and physical fatigue, memory loss, difficulty concentrating, dizziness, intoxication and vomiting;
  • Hypersensitivity reactions that include runny nose, teary eyes, asthma-like responses and hyperventilating sounds from the respiratory track;
  • Olfactory and taste symptoms, including changed sensitivity in smelling and tasting and impressions of unpleasant odors and tastes.[12]

An inadequately cleaned environment is the result of inattention to different emissions and by-products of indoor activities and the need for constant ordering. Poor ventilation often is the result of dirty air filters that require periodic cleaning or replacing. Emissions from cooking or tobacco products must always be removed. If left alone, the emissions accumulate, thereby damaging materials, causing odors and, in some cases, increasing cancer risks. Outside particles are constantly being tracked or blown inside. Soil contaminants or those on hard surfaces outdoors are tracked, blown or drawn into buildings. These contaminants rise to comparable outside concentrations in house dusts, carpets and other fabrics and must be removed through cleaning.

Prior to the 1994 energy crisis, buildings generally were designed to provide maximum comfort to their inhabitants. Work areas were larger. Heating, ventilation and air conditioning systems also were designed to provide an abundance of outside air for each occupant. Energy costs were not a priority.

Since 1974, buildings have been designed to conserve energy. The space size for heating and cooling was reduced and outdoor air ventilation was lowered. Moreover, many ventilation systems do not effectively distribute air to a building’s inhabitants. Inadequate air diffusion coupled with reduced ventilation causes pollution levels to accumulate. As pollutant concentrations rise so do health complaints. Reduced emphasis on cleaning only exacerbates this problem.

Biological contamination is a major cause of indoor illness. This form of contamination is caused by, or derived from, a living organism, such as bacteria, fungi, viruses and mites, and from other biological matter, such as insect parts. It originates inside and outside the built environment. Biological contamination occurs when moisture and food sources for living organisms are improperly managed. Ironically, mechanical ventilation systems often house these contaminants.

Biological pollutants, such as fungi and bacteria, breed in water that has accumulated on hard surfaces in humidifiers and cooling coil condensate pans. Pollutants also breed where water has collected on or beneath cellulose materials, such as ceiling tiles, wallpaper, carpeting, insulation and internally lined ductwork. The most publicized bio-pollutant, Legionella, causes Legionnaire’s Disease, which often is fatal in the elderly and hospitalized individuals.

Individuals can be sensitized to several different fungi, such as aspergillus and penicilium. They can experience a range of reactions from skin and eye irritation to labored breathing and fatigue. Some living organism wastes may be carcinogenic. Cleaning is instrumental in managing the indoor environment so many contaminants responsible for illness are removed from human contact.

Cleaning always is the critical ingredient in maintaining a healthy building condition. Removing or minimizing contaminants through cleaning reduces an individual’s exposure and risks.

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

[1] National Research Council (1986). Indoor Pollutants. Washington, D.C.: National Academies Press.

[2] Blainey, G. (2002). A Short History of the World. Chicago: Ivan R. Dee.

[3] Nuland, S. B. (1988). Doctors: The Biography of Medicine. New York: Alfred A. Knopf.

[4] Central Intelligence Agency (CIA) (2008). The World Factbook—United States,

[5] World Health Organization (1990). Basic Documents: 38th ed. (p. 1). Geneva, Switzerland.

[6] Biddle, W. (2002). Field Guide to Germs. New York: Anchor Books.

[7] Tierno, P. M. (2001). The Secret Life of Germs. New York: Pocket Books.

[8] Cohen, S. et al. (1986). Behavior, Health and Environmental Stress. New York: Plenum Publishing Corp.

[9] Berry, M. A. (2004). A Systems Modeling Approach to Assessing Carpet and Environmental Risk. International E-Journal of Flooring Sciences,

[10] Nuland, Doctors.

[11] Barry, J. M. (2005). The Great Influenza. Penguin Books.

[12] Cone, J. E. & Hodgson, M. J. (1989, December 1). Problem Buildings: Building-Associated Illness and the Sick Building Syndrome. Occupational Medicine. Oxford Journals: Oxford University Press.

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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.