What must be communicated to the homeowner prior to starting a radon test?

The correct response highlights that it is essential to communicate the testing protocol requirements to the homeowner before commencing a radon test. This is crucial because understanding the protocol ensures that the homeowner is aware of what to expect during the testing process, including factors such as how long the test will take, the placement of the test devices, and any necessary preparations they need to make (like keeping windows and doors closed). When homeowners are informed about these requirements, it helps ensure the accuracy and reliability of the results, facilitating a proper interpretation of radon levels in their home.

While other aspects like the importance of long-term testing, average radon levels in the area, and historical radon levels may provide context or additional information for the homeowner, it is the testing protocol that directly influences the integrity of the radon measurement process.