Factors Affecting Indoor And Outdoor Air Quality
Indoor Air Quality
Indoor air quality (IAQ) refers to the presence or absence of air pollutants in buildings. There are many sources of indoor air pollutants. Indications of potential health effects due to poor indoor air quality include:
- The presence of sources of indoor air pollutants such as tobacco smoke and radon, or
- Conditions that promote poor indoor air quality, such as inadequate ventilation or moisture intrusion, that can lead to mold growth.
The quality of air inside offices, schools, and other workplaces is important not only for workers’ comfort but also for their health. Poor IAQ has been tied to symptoms like headaches, fatigue, trouble concentrating, and irritation of the eyes, nose, throat and lungs.
Specific diseases have been linked to specific air contaminants or indoor environments, like asthma with damp indoor environments. Some exposures, such as asbestos and radon, do not cause immediate symptoms but can lead to cancer after many years.
Many factors affect IAQ. These factors include:
- Poor ventilation (lack of outside air),
- Problems controlling temperature,
- High or low humidity,
- Recent remodeling, and
- Other activities in or near a building that can affect the fresh air coming into the building.
Sometimes, specific contaminants like dust from construction or renovation, mold, cleaning supplies, pesticides, or other airborne chemicals (including small amounts of chemicals released as a gas over time) may cause poor IAQ.
The right ventilation and building care can prevent and fix IAQ problems.
Outdoor Air Quality
The Clean Air Act requires the Environmental Protection Agency (EPA) to set National Ambient Air Quality Standards for six common air pollutants. These commonly found air pollutants (also known as “criteria pollutants”) are found all over the United States. They are:
- Particle pollution (often referred to as particulate matter),
- Ground-level ozone,
- Carbon monoxide,
- Sulfur oxides,
- Nitrogen oxides, and
- Lead.
These pollutants can harm your health and the environment, and cause property damage. Of the six pollutants, particle pollution and ground-level ozone are the most widespread health threats. EPA calls these pollutants “criteria” air pollutants because it regulates them by developing human health-based and/or environmentally-based criteria (science-based guidelines) for setting permissible levels. The set of limits based on human health is called primary standards. Another set of limits intended to prevent environmental and property damage is called secondary standards.
