Calcium Carbide Gas Pressure Moisture Testers comply with ASTM D4944, AASHTO T217, and Florida FM 5-507 methods. The economical, American-made Gilson Aqua Check and the Speedy 2000 Moisture Testers both provide efficient and accurate moisture determinations in the field. A moist soil sample is agitated together with calcium carbide reagent in the test cell. Gas generated by the reaction pressurizes a dial gauge for direct percent moisture readings. The readings could be strategized and associated with readings from laboratory oven-dried moistures for increased accuracy. The Kelway Soil Acidity/Moisture Meter is a probe inserted in the soil that reads differences in electrical potential to estimate pH and relative moisture values.
For precise and accurate laboratory moisture content measurements, Ohaus Moisture Analyzers provide highly repeatable results. Samples are weighed, then quickly heated by the halogen dryer. The weight before and after drying provides the % moisture content, % solids or % regain.