Indoor Air sciences CSMI Practice Exam

What does the term 'dose and duration' refer to in indoor air quality?

1. Dose is the level and duration is time dependent

2. Dose is the concentration and duration is the time a person is exposed

3. Dose is the dilution and duration is time allowed to dilute

4. Dose is the amount of contaminant and duration is the number of exposures

The correct answer is: Dose is the concentration and duration is the time a person is exposed

The term 'dose and duration' in indoor air quality primarily refers to the relationship between the concentration of a contaminant and the length of time an individual is exposed to it. When assessing indoor air quality, understanding these two components is crucial for evaluating potential health risks. The 'dose' signifies the concentration of the harmful substances present in the air, typically measured in parts per million (ppm) or micrograms per cubic meter (µg/m³). This concentration indicates how much of the pollutant is present in a given volume of air. The 'duration' component denotes the time period an individual is exposed to this concentration. This could range from minutes to hours, days, or even longer depending on the living or occupational environment. Together, dose and duration help to establish the overall exposure risk. Higher concentrations over shorter periods or lower concentrations over extended periods can both lead to adverse health effects, but understanding this balance is pivotal in indoor air quality assessments and management. Other options do not accurately reflect the accepted definition; for example, some suggest that dose might refer to dilution or amount of exposures, which misrepresents the relationship of concentration and exposure time critical to assessing health impacts effectively.