Which of the following is NOT a recommended area to avoid during radon testing?

The recommended area to avoid during radon testing is typically one that would not provide a representative measurement of radon levels in the dwelling. Hallways and garages, for example, can often be sources of airflow that may dilute radon levels, while crawl spaces are specifically areas of concern due to the proximity to the ground and potential radon entry from the soil.

Bedrooms, on the other hand, are frequently used for testing because they are typically where people spend significant amounts of time. The goal of radon testing is to assess exposure in the living spaces where occupants are most likely to be affected. Therefore, it's essential to test in locations that reflect typical usage and exposure, where radon could accumulate to higher levels due to limited air circulation.

In summary, while areas like crawl spaces, hallways, and garages may be less representative for testing and can introduce variables that skew results, bedrooms are precisely the intended areas where radon levels should be measured to understand the potential risk to occupants.