Methods for Estimating Exposure

Exposure to air pollution is commonly measured by placing a monitor in the breathing zone of a subject. If the subject's activity patterns are recorded simultaneously, then it is possible to understand how a person's exposure profile is determined by places they visit, or by their activities or activities of those around them.

For example, if a person spends time around a smoker at home, or if they work in a factory with chemicals present, the monitor will register the elevated levels that coincide with the person being at home or at work.

Unfortunately, it is typically too burdensome or expensive to use a monitor on each subject. It may only be possible to monitor in fixed locations. Or what if monitoring cannot be accomplished at all?

In these cases, it is still possible to estimate the exposure of one's subjects by matching their time spent in different locations when sources of pollution were known to be present with the recorded levels in these locations or with typical levels recorded from previous studies.

This method of estimating exposure from elements measured separately (not simultaneously) is called the Indirect Exposure Assessment Approach . It forms the basis for the most simple kind of human exposure modeling.

The simulations on this website follow the basic indirect exposure formula for estimating exposure. Except, in our case, the levels are not necessarily drawn from empirical meaurements, but they are typically simulated using principles in physics, chemistry, and building engineering.

Stay tuned for more information on methods for measuring or simulating human exposure to air pollution.

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