Which practice helps ensure representative moisture testing results when drying aggregates?

• A. Stir the sample frequently during rapid drying.
• B. Dry at any temperature without monitoring.
• C. Use the largest possible sample size.
• D. Not record the original mass.

Answer: (A)

Moisture content testing relies on drying the sample evenly so that the weight loss represents moisture from the entire material, not just the surface. Stirring during drying helps distribute heat and moisture uniformly, breaking up clumps and preventing hot spots. When the sample is stirred, moisture can escape from all parts at a similar rate, which leads to a true constant-mass end point that reflects the whole sample. If you dry without stirring or at uncontrolled temperatures, some portions may dry faster than others, biasing the result. Using the largest possible sample size can actually hinder even drying, and failing to record the original mass makes it impossible to calculate the moisture content. So, frequent stirring during drying is the best practice to obtain representative results.