How safe is the environment in which people play, work, and study? Because so much of life is spent behind closed doors, indoor environmental quality is paramount to continued health and well being. At home, the individual is responsible for the quality of the environment.

Maintenance, whether done independently or contracted out, is ultimately under individual control. Each person is responsible for what is completed, how often it occurs, and the quality of the workmanship that is involved.

Once outside the security of home, however, people become dependent on others to provide an indoor environment that is as safe as the one left behind at home. From the air that is breathed to the water that is consumed, individuals are literally at the mercy of the business owners and managers of the various establishments frequented on a daily basis.

According to the Centers for Disease Control (CDC), Legionella is water-borne bacterium responsible for causing Legionnaires Disease (LD) and Pontiac Fever. Stachybotrys, is defined by the CDC as a greenish black mold that grows on damp materials with a high cellulose count, such as wood or paper.

Although these two nemeses appear to be unrelated issues, an underlying direct and causal relationship does exist. Improper surveillance and maintenance of indoor air equipment and potable water sources are the elements that are responsible for the proliferation of both problems in the indoor environment.

Although maintaining indoor air equipment and potable water sources is costly, the trade-off provides greater long-term benefits that are measurable in terms of decreased employee absenteeism, increased productivity, and improved job satisfaction and morale.


Annually, the typical asthma sufferer incurs a number of costs for the care and management of symptoms based on the illness' severity and repetition. The annual average total cost is comprised of various typical cost factors for the average patient suffering from asthma-related symptoms.

These average annual cost factors include diagnosis ($655.87), medication ($649.58), emergency room visit ($55), and periodic hospitalization ($105.55). According to these 2005 average figures, the average annual total comes to approximately $1,466.

Based on the prior data, it is possible to estimate that the cost of an indoor environmental problem, resulting in as few as 12 typical asthma-related illnesses, is greater than the costs of the indoor risk assessment and maintenance combined. This number lessens if the sufferers involved have chronic or persistent asthma and/or other pre-existing conditions or illnesses that have the potential of worsening the asthma.


Restoring human health and eradicating the responsible indoor sources are the paramount issues of the solution to the problem. Determining the sources of the problem and resolving them are eminent to human health and the indoor environment restoration.

According to information taken from Indoor Air Facts No. 4, a publication provided by the Environmental Protection Agency (EPA), prior to the 1973 oil embargo, building ventilation standards were formally set at "15 cfm of outside air for each building occupant, primarily to dilute and remove body odors."

One of the first building specifications that changed to accommodate the reduction in fuel costs was a reduction in the amount of outside air provided for ventilation from 15 cfm per person to 5 cfm per person.

The air quality problems that proliferated as a result of the reduction in the ventilation standard caused the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) to revise the "standard to provide a minimum of 15 cfm of outdoor air per person; 20 cfm per person in office spaces." The standard also specified up to 60 cfm per person in such places as smoking lounges.

If the presence of Legionella or Stachybotrys is suspected or found in the indoor environment, it is crucial to find every source of the problem and remedy it immediately. A thorough assessment of all indoor equipment must be performed to make sure that all problematic sources are eliminated. The cost of closing down operations should never be a factor in the decision- making process.

When Legionella is linked to the work site, federal law mandates a resolution. According to Section III, Chapter 7 of the Occupational Safety and Health Administration's (OSHA's) Technical Manual, the investigation protocol is dependent on the severity of the problem.

For instance, "a level-one investigation may be initiated when there is a probable basis for suspecting that workplace water sources are contaminated with Legionella, or when there is information that one case of LD may exist. A level-two investigation should be conducted when more than one possible case of LD has been reported at a facility."

There are typically four fundamental steps involved in a level-one investigation. The steps include obtaining an overview of all facility water systems, conducting a walk-through investigation of the facility, assessing the results of the walk-through investigation, and recommending control actions. A more elaborate program involving the employees is used for a level-two investigation.

In Drinking Water Standards for Regulated Contaminants, a report released by the EPA, guidelines on the acceptable amounts of contaminants allowed in sources of potential drinking water are discussed, as well as the rule for surface water treatment.

For Legionella (bacteria), Giardia (parasites), and viruses, Maximum Contaminant Level Goals (MCLGs) are set at zero due to the potential health risk.


Correcting an indoor problem is expensive, but the benefits outweigh the costs. The costs associated with the proper surveillance and maintenance of the indoor equipment include the initial risk assessment, the remedial changes needed based on any recommendations, and the subsequent assessments.

In spite of the absence of a problem with the indoor equipment, risk assessment is essential for the proper management of it. Risk assessment entails developing a map of the plant and surveying the probable and potential problems that exist. Likewise, risk assessment entails developing an effective plan with the given constraints of the operational budget.

Programs, like the EPA's Indoor Air Quality Building Education and Assessment (I-BEAM), can be extremely useful because a "what if" analysis to budgeting is included. From the assessment audit provided with I-BEAM it is possible to determine the number of hours needed and the approximate cost of equipment maintenance and surveillance.

For example: It would take 10 hours to perform a typical baseline indoor air quality (IAQ) analysis of the indoor spaces, 20 hours to perform a typical baseline IAQ analysis of the HVAC systems, and 10 hours to perform a typical baseline IAQ analysis of the outdoor spaces. Given an average cost per man-hour of $45, based on 2005 rates, the total cost of the assessment in this example is $1,800.

Remedial changes must be made to ensure public safety and minimize the likelihood of an indoor problem occurring. It is important to investigate all of the recommendations made to properly assess probable and potential problems. Like the risk assessment phase, the remedial phase faces much of the same operational budget constraints.

Again, I-BEAM can be an extremely powerful tool because it contains a "what if" analysis to budgeting. For example: It would take an average eight hours per month to perform the tasks necessary for the periodic IAQ inspections at a cost of $4,320 per year, an average of eight hours per month to perform the tasks necessary for the repair and replacement of parts and equipment at a cost of $4,320 per year, an average of $200 per month for parts at a cost of $2,400 per year, and an average of eight hours per month to perform the tasks necessary for a manager's IAQ oversight at a cost of $4,320 per year.

The total cost of remedial care of the equipment in the example is estimated at $15,360 per year, which, including the cost of the initial risk assessment, would total $17,160 per year.

Although subsequent assessments are costly, the benefits provided in terms of self-assurance of a safe environment are immeasurable. Regardless of the costs involved in the risk assessment and remedial stages, safety and health are paramount to success. Additionally, proper maintenance of the indoor equipment ensures the health and well being of the building.

Furthermore, by providing a healthier and safer environment, a company's risk of litigation can be reduced with proper indoor monitoring and maintenance.


The benefits associated with the proper indoor equipment surveillance and maintenance includes increased productivity, decreased employee absenteeism, and improved job satisfaction and morale.

According to I-BEAM Text Modules: Fundamentals of IAQ in Buildings, a publication released by the EPA, recent studies suggest that the deterioration of the indoor environment due to modest changes in temperature and humidity; the lack of proper ventilation; and the presence of indoor pollutants, has resulted in an estimated average performance loss of 2 percent to 4 percent.

The level of increased productivity due to the compatibility of the indoor environment and its inhabitants acts as an offset to the costs. There is a direct relationship between the health of a company's workers and overall productivity. Employees tend to perform duties better in an environment that is conducive to overall comfort and well being. The cost of providing an environment that is conducive to increasing productivity is offset by increased profitability.

Decreased absenteeism not only has a positive effect on the level of productivity, but also has a positive impact on operational costs. There is a direct relationship between a decreased level of absenteeism and an increased level of productivity.

There is a direct relationship between the level of employee absenteeism and the level of operational costs. The cost of replacing a sick worker or doing without the needed services has a negative impact on profitability. From the cost analyses of the illnesses and indoor equipment maintenance, it is clear to see that the benefits of performing the latter outweigh the costs.

Although not measurable in dollars, overall job satisfaction is also improved by a healthy indoor environment. According to Indoor Air Pollution: An Introduction for Health Professionals, the average person spends an estimated 90 percent of their time inside. There is a direct relationship between job satisfaction and job performance. Likewise, there is a direct relationship between the quality of the indoor environment and the level of profitability.

From the cost analyses that were performed, it is clear to see that maintaining the indoor equipment is cost-effective when compared with the rising costs of healthcare.

Allan Carisse is an HVAC manager for the Detroit Tigers Inc., overseeing preventative maintenance and repairs of all mechanical equipment within Comerica Park (Detroit). He is a licensed mechanical contractor and also owns Carisse Mechanical Services.

Publication date: 01/23/2006