A faint line on a drug test indicates a negative result. If both the Control and Test lines are visible, even if they are small and faint, they are still valid. This visibility suggests that the drug is not present at the sensitivity level of the test. However, it's important to note that the absence of a drug at this sensitivity doesn't necessarily mean it's entirely absent from the subject's system. The faint line might indicate trace amounts, but as long as they remain below the established threshold, the overall result is considered negative.
If the test is left beyond the maximum duration, and the faint line disappears, this doesn't automatically render the test positive. Faint lines may vanish over time due to chemical reactions on the product, but the disappearance of the line doesn't change the initial interpretation of a negative result. It's crucial to adhere to the specified test duration and understand that the visibility of lines within that timeframe is what determines the outcome.