Poor indoor air quality, or IAQ, can cause headaches, fatigue, difficulty concentrating, dry skin and breathing issues, as well as irritated eyes, nose and throat. People suffering from allergies or asthma may have more severe symptoms due to poor IAQ. The Occupational Safety and Health Administration (OSHA) lists several factors that affect IAQ. These include:
- Poor ventilation
- Difficulty regulating indoor temperatures
- Too much or too little humidity
- Mold
- Airborne contaminants such as dust and chemicals
Before There Were Air Quality Standards
You might be surprised to know that central heating is nothing new. In fact, a central heating system was used as far back as 1200 B.C. in the palace of King Arzawa, who ruled in present day Turkey, according to Air Quality Sciences, an Underwriters Laboratory.
This same technology was used by the Roman Empire a millennium later. Unfortunately, these earliest attempts at HVAC did not include a true understanding of IAQ.
In the 1500s, charcoal was used as a home heating fuel. When used in closed rooms in a brazier, it emitted high levels of carbon monoxide – and death of the occupants was the result. In the mid-1700s, Benjamin Thompson improved upon Benjamin Franklin’s heating stove, the new design adding a smoke shelf to help control fresh air intake, increasing efficiency.
Cities in the United States continued to grow throughout the 1800s and early 1900s. The tuberculosis outbreak in the late 1800s generated concern about indoor air quality. John Shaw Billings, the deputy surgeon general of the U.S. Army, presented statistics showing a correlation between poor indoor air quality and various diseases, specifically relating to insufficient ventilation. His recommendations for building ventilation standards were well received and by 1915, twenty-one states had enacted ventilation standards.
Fifty-five years later in 1970, the U.S. Environmental Protection Agency (EPA) was formed. Their first mission was to fix environmental problems, and air pollution in particular.
The energy crisis of the 1970s had a direct effect on how buildings were designed and built, as well as how their HVAC systems were used. To conserve energy, both commercial and residential building owners were encouraged to economize their heating and cooling usage. This led to a greater dependence on re-circulated air. IAQ did not become a priority at the EPA until the 1980s.
Current Air Quality Standards
While OSHA has not set designated IAQ standards, the organization has ventilation standards and standards regarding air contaminants. Only three states have indoor air regulations: California, New Jersey and Washington.
The American Society for Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) also provides standards, including the “Ventilation for Acceptable Indoor Air Quality” standard also known as ASHRAE Standard 62.1-2004. This standard has been developed to provide minimum ventilation rates plus IAQ that is acceptable for all human occupants. These rates also must reduce the risk for adverse health effects.
Independent testing companies such as the GREENGUARD Environmental Institute (GEI) has developed IAQ standards regarding building materials, furnishings, office equipment, electronics, cleaners and schools.
Measuring IAQ
IAQ can be measured using one of four different devices:
- Vacuum pump
- Direct-reading meter
- Detector tube kit
- Dosimeter or personal monitoring device
What it Means to You
Understanding the pollutants that contribute to poor IAQ can help improve your home’s air quality. Tobacco smoke, carbon monoxide, radon, nitrogen dioxide and VOCs (volatile organic compounds) found in cleaning products, pesticides and furniture finishes are pollutants that affect IAQ.
Install a carbon monoxide detector and test for radon with a home-testing kit. Do not allow any tobacco smoke within your home and monitor all cleaning compounds used. When painting, opt for VOC-free certified interior paint. Keep your HVAC filters fresh, changing them regularly as recommended by the manufacturer. A clogged or dirty air filter will not help your indoor air quality.
