Final answer:
The four elements for indoor air quality problems to exist are pollutant sources, inadequate ventilation, indoor pollutant levels, and sensitive individuals.
Step-by-step explanation:
The four elements that must be present for indoor air quality problems to exist are:
- Pollutant sources: Sources of indoor air pollution can include combustion sources (such as oil, gas, kerosene, coal, wood, and tobacco products), building materials and furnishings (such as deteriorated insulation, wet carpet, and furniture made of pressed wood products), and household cleaning and maintenance products.
- Inadequate ventilation: If a building does not have sufficient ventilation, it can lead to high concentrations of indoor air pollutants. Inadequate ventilation can also be caused by not bringing in enough outdoor air to dilute emissions from indoor sources and not carrying indoor air pollutants out of the home.
- Indoor pollutant levels: Higher concentrations of toxic pollutants are generally found in indoor air compared to outdoor air. This is due to the release of gases or particles from indoor pollution sources.
- Sensitive individuals: Some individuals are more susceptible to the health effects of indoor air pollution, such as those with respiratory conditions, allergies, or compromised immune systems.