Periodic checks of a concrete producer's sand moisture meter assures reliable readings and batch weight adjustments. Batching wet sand adds water to concrete, requiring batch weight adjustments to avoid unacceptable variations in water-cement ratio, slump, and volume of concrete produced. These meters are standard equipment for most concrete plants. The meters are often linked to computer-controlled batching systems, permitting automatic adjustment of batch weights for sand and water added at the plant. To confirm meter accuracy, readings should be checked periodically. There are several methods producers can use to do this. Also included are seven tips to ensure stable moisture.