What actions should be avoided during the 20-minute waiting period?

During the 20-minute waiting period before administering a breath test with the Intoxilyzer 9000, it is crucial that the subject avoids any foreign objects in their mouth. This waiting period is designed to ensure that the results of the breath test accurately reflect the subject's blood alcohol content levels without interference from substances that may be present in the mouth.

Foreign objects can include anything from chewing gum to tobacco or dental appliances. If these items are in the mouth during the waiting period, they can potentially introduce alcohol vapor or interfere with the measurements by altering the airflow or the breath sample. Ensuring that the subject's mouth is clear from any foreign substances helps maintain test integrity and ensures that the results are valid and reliable.

The other actions may not be appropriate in the context of maintaining the accuracy of the test results. For example, eating or drinking could introduce new substances into the system, and smoking can produce alcohol vapor in the breath. Taking medication can also impact the results, depending on the substance. Therefore, it is essential to have a clear mouth to guarantee that the breath test provides an accurate reflection of the subject's alcohol level.