Indoor Air Quality in the Workplace

Most people spend a large majority of their lives in the workplace, making it crucial that the space is a comfortable and healthy environment. If not properly managed, poor indoor air quality can cause troubling health symptoms, that lead to decreased productivity and increased absenteeism.

Health issues caused by poor indoor air quality can range from acute (occurring immediately) to chronic (long lasting). Examples of acute effects would be a runny nose or headache caused by mold exposure. On the other hand, a chronic effect would be a much more serious issue, such as cancer due to prolonged asbestos exposure. Other symptoms of poor indoor air quality, such stuffy air or dry air, could be classified as discomfort.

What Causes Indoor Air Quality Issues?

Inferior air quality can be caused by a variety of problems from cleaning products to motor vehicle exhaust to airborne bacteria. Generally, the problems can be divided into four categories: thermal environment, inadequate ventilation, chemical contaminants, or biological contaminants.

The thermal environment of a building is comprised of temperature, relative humidity, and airflow.Thermal environment plays a huge role in the health and happiness of employees. Often times, simply regulating the temperature or humidity so it’s more comfortable for the workers can erase many of their symptoms. A large portion of thermal environment is determined by the HVAC system but it is also affected by amount of sunlight, position of air vents, and amount of activity by employees.

Inadequate ventilation is another factor that can lead to air quality issues. Lack of ventilation is becoming more and more common as government regulations require buildings to be more airtight. While this does improve energy efficiency of the building, it can also increase indoor air pollution by restricting air movement. In the early 1900’s, the building ventilation standards called for 15 cubic feet per minute of outside air for each building occupant. Then, the 1973 oil embargo led to the need to decrease heating, and thus the requirement was reduced to 5 CFM per person. Ultimately, it was determined that this was not sufficient air flow for people’s health, and the standard was raised to 20 CFM per person in a work place. While the recommended standard is now raised, not all buildings meet this guideline so it’s a crucial area to check. Lack of air flow can make contamination and pollution more likely.

Another factor leading to air quality issues is chemical contaminants. Chemical contaminants, such as building exhaust or asbestos, could enter the building through poorly placed intake vents or windows. There could also be chemical contaminants already inside the building. For instance, upholstery, pesticides, and cleaning agents could all contain harmful VOC’s.

In addition, biological contaminants can play a role in indoor air quality. Oftentimes, biological contaminants are caused by excess moisture. For instance, bacteria, fungus, mold, and viruses can all be sources of biological contaminants and are often caused by stagnant water in air ducts, dripping pipes, wet insulation, or other areas of moisture. These contaminants are often circulated by air conditioning systems.

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Sick Building Syndrome Vs. Building Related Illness

Most symptoms of poor indoor air quality can be classified as either Sick Building Syndrome or Building Related Illness. Sick building syndrome (SBS) is comprised of a variety of symptoms that occur when people are in the workplace but dissipate once they leave. Symptoms of SBS can include headache, lethargy, dry cough, nausea, or throat irritation. Sometimes SBS can be traced to a specific area of the building but, it is often widespread throughout the workplace. In SBS, no specific cause can be determined.

Conversely, in Building Related Illness (BRI), poor health symptoms can be traced to a specific airborne building contaminant. For instance, the issue may be traced back to contaminants in the humidification system or mold in the building materials. Symptoms of BRI are often very similar to the flu, and can include coughing or chills. Unlike SBS, Building Related Illness symptoms do not disappear immediately after leaving the building.

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Checking for Indoor Air Quality Issues

If you start to notice troubling symptoms in your employees, it may be time for a building investigation. An investigation can be useful for identifying and solving indoor air quality issues. Prior to starting an investigation it’s helpful to gather background information such as areas with highest concentration of symptoms, HVAC zones, and any relevant history of the building. Next, it’s time for a walk through inspection that includes the HVAC system, ventilation system, and other possible sources of contaminants and pollutants. During the walkthrough, keep an eye out for obvious signs of contamination, such as mold, fungus, or excessive moisture. If nothing is found on the initial walk through, air sampling can be helpful to check for signs of contaminants. Note the temperature, humidity, and air flow, in addition to checking levels of carbon monoxide, formaldehyde, and ozone. Finally, check the water sources for biological organisms or contaminants.

If you do discover a source of contamination, be sure to take care of it as quickly as possible. Once the source has been removed, it’s time to take a look at how you can prevent the problem from reoccurring. For instance, ensuring that there is proper air movement through the ventilation system. HVAC systems need be routinely checked and properly maintained. If there is a consistent build up of pollutants in the air conditioning, the air may need to be directed outside. If air quality is a persistent issue, the use of air filters or dehumidifiers can be extremely helpful.

It is also important to take care of any sources of excess moisture. If you discovered any moisture during your inspection, such as wet ceiling tiles, be sure to repair them promptly. Moisture is something that needs to be monitored closely during routine maintenance to help prevent situations from becoming severe. If, however, significant mold or fungus is discovered, it is best to let professionals handle it.

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"Fundamentals of Indoor Air Quality in Buildings." EPA. Environmental Protection Agency, n.d. Web. 28 Nov. 2016.
"Indoor Air Facts No. 4 Sick Building Syndrome." Environmental Protection Agency. US Environmental Protection Agency, Feb. 1991. Web. 28 Nov. 2016.
Sumedha, John. "The Sick Building Syndrome." Indian Journal Of Occupational & Environmental Medicine. N.p., Aug. 2008. Web. 28 Nov. 2016.