In personal air sampling, what is considered the breathing zone of the worker?

The breathing zone of a worker is defined as the space around their head where inhaled air is likely to come from. This is typically understood to be within a 10-inch radius of the worker's nose and mouth area, which is crucial for effective personal air sampling. The rationale behind this measurement is to capture the air that the worker is actually inhaling, thereby providing an accurate assessment of their exposure to airborne contaminants, such as asbestos fibers.

In contrast, the other options do not align with standard definitions or practices in occupational health. For instance, a radius based on the chest or feet would not accurately reflect the air quality that the worker is breathing. Effective air sampling must recognize the proximity to the respiratory system to ensure that the data collected is relevant to the worker’s exposure risks. Thus, the 10-inch radius around the nose and mouth accurately captures the inhaled air, making it the appropriate choice for defining the breathing zone in personal air sampling.